Multiple-input multiple-output communication with wireless communication devices

ABSTRACT

Aspects of this disclosure relate to pair of wireless communication devices wirelessly communicating with a network system in a coordinated manner. A secondary wireless communication device can wirelessly communicate part of a multiple-input multiple-output (MIMO) transmission associated with a primary wireless communication device (i) with the primary wireless communication device via the peer-to-peer link and (ii) with the network system via a cellular link. The secondary wireless communication device can enable the primary wireless communication device to communicate with the network system at a higher data rate and/or at a higher MIMO rank.

CROSS REFERENCE TO PRIORITY APPLICATION

This application is a continuation of U.S. patent application Ser. No.16/224,528, filed Dec. 18, 2018 and titled “USER EQUIPMENT WITH CELLULARLINK AND PEER-TO-PEER LINK,” the disclosure of which is herebyincorporated by reference herein in its entirety and for all purposes.

BACKGROUND Technical Field

Embodiments of this disclosure relate to wirelessly communicatingmultiple-input multiple output (MIMO) data.

Description of Related Technology

The types of modern computing devices continues to increase along withthe differing and dynamic needs of each device. The wirelesscommunication systems providing services to such devices are facingincreasing constraints on resources and demands for quality andquantities of service. In certain multiple-input multiple-outputwireless communication systems, a peak data rate and/or rank determinedby a number of antennas and/or a number of transmit/receive chains of auser equipment arranged to connect to a network system can limit therate and/or quality at which data is exchanged. Accordingly,improvements in providing wireless communication services in amultiple-input multiple-output system are desired.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of this disclosure will now be described, by way ofnon-limiting example, with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating an example multiple-inputmultiple-output (MIMO) network in which user equipment (UE) and anetwork system wirelessly communicate according to an embodiment.

FIG. 2A is a diagram illustrating coordinated transmission and receptionof MIMO data for one UE by a pair of UEs communicating via apeer-to-peer (P2P) link according to an embodiment.

FIG. 2B is a diagram illustrating coordinated reception of MIMO data forone UE by a pair of UEs communicating via a P2P link according to anembodiment.

FIG. 2C is a diagram illustrating coordinated transmission of MIMO datafor one UE by a pair of UEs communicating via a P2P link according to anembodiment.

FIG. 3A is a diagram illustrating a MIMO network in which datatransmission and reception associated with a primary UE is limited bythe number of transmit-receive points (TRPs) for serving the primary UE.

FIG. 3B is a diagram illustrating the primary UE of FIG. 3A with a P2Plink with a secondary UE to enable the primary UE to receive MIMO datawith a higher rank than in the case of FIG. 3A according to anembodiment.

FIG. 4 is a block diagram illustrating a network system that includes anexample base band unit and remote radio units according to anembodiment.

FIG. 5 is a block diagram of an example UE according to an embodiment.

FIG. 6 illustrates example communications and events of an embodiment ofestablishing a clone pair of UEs and jointly receiving MIMO dataassociated with one UE of the clone pair using both UEs of the clonepair.

FIG. 7 illustrates example communications and events of an embodiment ofestablishing a clone pair of UEs and jointly receiving MIMO dataassociated with one UE of the clone pair using both UEs of the clonepair.

FIG. 8 illustrates example communications and events of an embodiment ofdetecting a clone pair of UEs and establishing a tunnel to a primary UEthrough the secondary UE.

FIG. 9A illustrates an example MIMO communications environment in whichdifferent beams from the same serving node are transmitted to differentUEs of a pair of UEs in communication via a P2P link according to anembodiment.

FIG. 9B illustrates an example MIMO communications environment in whichdifferent beams from the same serving node are transmitted to differentUEs of a pair of UEs in communication via a P2P link according toanother embodiment.

FIG. 10A is a flow diagram illustrating an example method of processingdownlink data by a primary user equipment according to an embodiment.

FIG. 10B is a flow diagram illustrating an example method oftransmitting uplink data by a primary user equipment according to anembodiment.

FIG. 11A is a flow diagram illustrating an example method of processingdownlink data by a secondary user equipment according to an embodiment.

FIG. 11B is a flow diagram illustrating an example method of processinguplink data by a secondary user equipment according to an embodiment.

FIG. 12A is a flow diagram illustrating an example method of processinguplink data by a network system according to an embodiment.

FIG. 12B is a flow diagram illustrating an example method oftransmitting downlink data by a network system according to anembodiment.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

The innovations described in the claims each have several aspects, nosingle one of which is solely responsible for its desirable attributes.Without limiting the scope of the claims, some prominent features ofthis disclosure will now be briefly described.

One aspect of this disclosure is a user equipment that includes one ormore antennas, a peer-to-peer wireless interface, and a processor incommunication with the one or more antennas and the peer-to-peerwireless interface. The one or more antennas are configured to receive afirst part of a multiple-input multiple-output (MIMO) downlink datatransmission from one or more serving nodes. The peer-to-peer wirelessinterface is configured to receive a second part of the MIMO downlinkdata transmission from at least one secondary user equipment. Theprocessor is configured to aggregate the first part of the MIMO downlinkdata transmission together with the second part of the MIMO downlinkdata transmission.

Another aspect of this disclosure is a method of receiving amultiple-input multiple-output (MIMO) downlink data. The method includesreceiving, using one or more antennas of a primary user equipment, afirst part of the MIMO downlink data transmission from one or moreserving nodes. The method also includes receiving, using a peer-to-peerwireless interface, a second part of the MIMO downlink data transmissionfrom at least one secondary user equipment. The method further includesprocessing, using a processor of the primary user equipment, the firstpart of the MIMO downlink data transmission together with the secondpart of the MIMO downlink data transmission.

Another aspect of this disclosure is a user equipment that includes oneor more antennas configured to transmit a first part of a multiple-inputmultiple-output (MIMO) uplink data transmission, a peer-to-peer wirelessinterface configured to transmit a second part of the MIMO uplink datatransmission to at least one secondary user equipment, and a processorin communication with the one or more antennas and the peer-to-peerwireless interface. The processor is configured to cause transmission ofthe first part of the MIMO uplink data transmission via the one or moreantennas and to cause transmission of a second part of the MIMO uplinkdata transmission via the peer-to-peer wireless interface.

Another aspect of this disclosure is a method of processing downlinkdata. The method includes establishing a communication channel between aprimary user equipment and a secondary user equipment via a peer-to-peerwireless link between the primary user equipment and the secondary userequipment. The method also includes while the primary user equipment isreceiving first multiple-input multiple-output (MIMO) downlink data forthe primary user equipment via a cellular communication, receivingsecond MIMO downlink data for the primary user equipment using one ormore antennas of the secondary user equipment. The method also includestransmitting the second MIMO downlink data to the primary user equipmentvia the communication channel.

Another aspect of this disclosure is a user equipment that includes oneor more antennas configured to receive a part of a multiple-inputmultiple-output (MIMO) downlink data transmission, a peer-to-peerwireless interface configured to communicate with a primary userequipment, and a processor in communication with the one or moreantennas and the peer-to-peer wireless interface. The processor isconfigured to receive the part of the MIMO downlink data transmissionvia the one or more antennas, determine that the part of the MIMOdownlink data is associated with the primary user equipment, and causetransmission of symbol level data corresponding to the part of the MIMOdownlink data via the peer-to-peer wireless interface to the primaryuser equipment.

Another aspect of this disclosure is a method of processing uplink data.The method includes establishing a communication channel between asecondary user equipment and a primary user equipment via a peer-to-peerwireless interface of the secondary user equipment. The method alsoincludes while the primary user equipment is transmitting firstmultiple-input multiple-output (MIMO) uplink data for the primary userequipment to a network system via a cellular communication, receiving,by the secondary user equipment, second MIMO uplink data transmissionfrom the primary user equipment via the communication channel. Themethod further includes transmitting, using one or more antennas of thesecondary user equipment, the second MIMO uplink data to the networksystem.

Another aspect of this disclosure is a method of processing uplink data.The method includes receiving, by a network system, a first uplink datatransmission associated with a primary user equipment from the primaryuser equipment. The primary user equipment is configured to transmituplink data at a rate of up to a peak uplink data rate. The method alsoincludes receiving, by the network system, a second uplink datatransmission associated with the primary user equipment from a secondaryuser equipment. The method further includes processing, by the networksystem, data associated with the first uplink data transmission togetherwith data associated with the second uplink data transmission so as toprocess uplink data associated with the primary user equipment at a rateof greater than the peak uplink data rate of the primary user equipment.

Another aspect of this disclosure is a method of transmitting downlinkdata. The method includes generating, by a network system, downlinktransmission data for a primary user equipment. The method also includeswhile the primary user equipment is in communication with a secondaryuser equipment via a peer-to-peer link: transmitting, by the networksystem, a first part of the downlink transmission data for the primaryuser equipment to the primary user equipment; and transmitting, by thenetwork system, a second part of the downlink transmission data for theprimary user equipment to the secondary user equipment.

Another aspect of this disclosure is a method of transmitting downlinkdata. The method includes determining a secondary user equipment toenter a clone mode based on a joint spectral efficiency of a group ofuser equipments. The group of user equipments includes the secondaryuser equipment and a primary user equipment. The method includessignaling to the secondary user equipment to enter the clone mode. Themethod also includes while the secondary user equipment is in the clonemode, transmitting (a) first downlink data for the primary userequipment to the secondary user equipment and (b) second downlink datafor the primary user equipment to the primary user equipment.

Another aspect of this disclosure is a method of multiple-inputmultiple-output (MIMO) wireless communication. The method includesreceiving, by a network system, first uplink MIMO data associated with aprimary user equipment from the primary user equipment. The method alsoincludes receiving, by the network system, second uplink MIMO dataassociated with the primary user equipment from a secondary userequipment, wherein the primary user equipment is in communication withthe secondary user equipment via a peer-to-peer link. The method furtherincludes aggregating, by the network system, the first uplink MIMO datatogether with the second uplink MIMO data. In addition, the methodincludes transmitting, by the network system, downlink data associatedwith the primary user equipment to a single user equipment via cellularcommunications.

Another aspect of this disclosure is a method of multiple-inputmultiple-output (MIMO) wireless communication. The method is performedwhile a primary user equipment is in communication with a secondary userequipment via a peer-to-peer link. The method includes transmitting, bya network system, a first part of a downlink MIMO data transmission forthe primary user equipment to the primary user equipment. The methodalso includes transmitting, by the network system, a second part of thedownlink MIMO data transmission for the primary user equipment to thesecondary user equipment. The method further includes receiving, by thenetwork system, uplink data for the primary user equipment from a singleuser equipment via cellular communications.

The present disclosure relates to U.S. patent application Ser. No.16/224,643, titled “USER EQUIPMENT CONFIGURED FOR INCREASED DATA RATE,”U.S. patent application Ser. No. 16/224,520, titled “METHODS OFWIRELESSLY COMMUNICATING WITH A GROUP OF DEVICES,” and U.S. patentapplication Ser. No. 16/224,568, titled “UNBALANCED WIRELESSCOMMUNICATION WITH GROUP OF DEVICES,” each filed on Dec. 18, 2018 andthe disclosures of each of which are hereby incorporated by reference intheir entireties herein.

For purposes of summarizing the disclosure, certain aspects, advantagesand novel features of the innovations have been described herein. It isto be understood that not necessarily all such advantages may beachieved in accordance with any particular embodiment. Thus, theinnovations may be embodied or carried out in a manner that achieves oroptimizes one advantage or group of advantages as taught herein withoutnecessarily achieving other advantages as may be taught or suggestedherein.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

The following description of certain embodiments presents variousdescriptions of specific embodiments. However, the innovations describedherein can be embodied in a multitude of different ways, for example, asdefined and covered by the claims. In this description, reference ismade to the drawings where like reference numerals can indicateidentical or functionally similar elements. It will be understood thatelements illustrated in the figures are not necessarily drawn to scale.Moreover, it will be understood that certain embodiments can includemore elements than illustrated in a drawing and/or a subset of theelements illustrated in a drawing. Further, some embodiments canincorporate any suitable combination of features from two or moredrawings. The headings provided herein are for convenience only and donot necessarily affect the scope or meaning of the claims.

In a network that has a relatively large number of transmit and receiveantennas at a base station for communicating with user equipment (UE), apeak rate of a given UE can be limited by the multiple-inputmultiple-output (MIMO) capabilities of the UE. Such MIMO capabilitiescan include a number of transmit and/or receive chains of the UE and/ora number of antennas of the UE configured to communicate with a networksystem. For example, if a network system is relatively lightly loadedand has 64×64 transmit and receive chains and a UE has a 2×2 transmitand receive configuration, the UE peak rate can be limited to rank 2MIMO in both receiving downlink data and transmitting uplink data. Rankcan refer to a number of spatial layers available for cellularcommunications with a UE. Rank is nominally limited by the minimumnumber of transmit and receive antennas for a link, in this example 2.The rank may be limited by the channel structure, which can furtherlimit the number of spatial layers to less than the antenna limit.

Aspects of this disclosure relate to using a peer-to-peer (P2P) linkbetween a primary UE to a secondary UE in proximity to enable a higherrate data and/or peak data rate for the primary UE. This can enable theprimary UE to exchange MIMO data at a higher rank compared to theprimary UE communicating with the network system without the P2P linkand the secondary UE. The higher effective MIMO order can be achievedwith a combination of a cellular link of a primary UE and the primary UEreceiving data via the P2P link and a cellular link of the secondary UE.Such a configuration can also enable a primary UE in a heavily congestedcell of transmit-receive points (TRPs) to receive traffic from arelatively nearby and less loaded cell of TRPs for higher throughput,upon discovering and establishing a P2P link with a secondary UE in thenearby cell. A variety of methods are disclosed for using a secondary UEto increase the data rate and/or rank associated with datacommunications between the primary UE and a network system. For example,application routing and aggregation can allow the network system toserve two UEs with a P2P link between them with multi-user MIMO(MU-MIMO). As another example, the UEs with a P2P link between them canform a virtual higher order MIMO transceiver for the primary UE andperform combining at a physical layer through high speed sample transferbetween the two UEs. Similar principles and advantages can be applied totransmitting uplink data from the two UEs. Although examples embodimentsmay be described in terms of a singular secondary UE; any suitableprinciples and advantages disclosed herein can be applied to cases wheretwo or more secondary UEs are paired with a primary UE.

The technology disclosed herein provides a framework of enabling higherpeak rate of a primary UE through a P2P link with a secondary UE fordownlink data communications and/or uplink data communications. Themechanisms of achieving a higher peak data rate can be achieved usingjoint processing at the physical layer and/or aggregation from anapplication perspective. The mechanism of achieving the higher peak datarate though a higher order physical layer category and MIMO order isalso disclosed.

A primary UE and a secondary UE arranged to transmit and/or receive MIMOdata associated the primary UE in a coordinated manner can be referredto as a clone pair of UEs. The UEs of the clone pair can each exchange(e.g., transmit and/or receive) MIMO data associated with the primary UEwith TRPs. The secondary UE can assist the primary UE in exchanging datawith a network. The UEs of the clone pair can also wirelesslycommunicate with each other over a P2P link. The secondary UE of theclone pair can operate in a clone mode to receive and/or transmit MIMOdata associated with the primary UE from and/or to one or more TRPs. Inthe clone mode, the secondary UE can also wirelessly communicate withthe primary UE over the P2P link.

Although embodiments disclosed herein may be discussed with reference toclone pairs of 2 UEs, any suitable principles and advantages discussedherein can be implemented in applications where a group of three or moreUEs are arranged to transmit and/or receive MIMO data associated withone of the UEs of the group in a coordinated manner.

A primary UE can discover one or more candidate secondary UEs. Thediscovery can be performed by the primary UE by itself and/or withassistance of a network system. The candidate secondary UEs can besufficiently close to the primary UE to establish a P2P link. One ormore of the candidate secondary UEs can be idle. In response todiscovery, a P2P link can be established between the primary UE and asecondary UE. Data from the primary UE can be transmitted to thesecondary UE via the P2P link. Subsequent data transmission to andreception from a network system can be performed, for example, viaMU-MIMO and application layer aggregation. As another example,subsequent data transmission to and reception from a network system canbe performed via a time-coordinated single-user MIMO (SU-MIMO) though ahigher order UE category and higher order data rate request though theprimary UE jointly using the TRP information of the secondary UE.

As an example of the technology described herein, a primary UE with 2receive chains and 2 transmit chains can communicate with a 4×4 cellsite with a peak data rate similar to 4×4 MIMO. The primary UE can beactive and achieve a data rate corresponding to 2×2 MIMO operating byitself. A secondary UE can be discovered and a P2P link can beestablished between the primary UE and the secondary UE. Bycommunicating with a network system using hardware of both the primaryUE and the secondary UE, the primary UE can achieve a data rate similarto 4×4 MIMO.

The technology disclosed herein can be applied in a variety ofapplications. For example, two UEs can execute coordinated transmissionand/or reception of MIMO data associated with one of the two UEs inapplications where excessive network MIMO dimensions are available. Insome instances, a higher number of TRPs of a network system areavailable for transmission than a total number of receive antennasacross active UEs. Alternatively or additionally, a higher number ofTRPs of a network system are available for receiving than total numberof transmit antennas across active UEs. FIGS. 2A to 2C illustrateexample environments in which excessive network MIMO dimensions areavailable and can be used by a pair of UEs to increase the rank of MIMOcommunication between the network and a UE of the pair.

As another example, nearby UEs in different spatial channels can beavailable for communicating with different respective TRPs of thenetwork system. A secondary UE nearby a primary UE can establish a highquality P2P connection. The secondary UE can have one or more differentpreferred spatial beams from one or more TRPs of a network system thanthe primary UE. The secondary UE can be in relatively low mobility. Inthis example, the primary UE can be associated with one or more crowdedTRPs that can limit service to the primary UE. The primary UE can use aP2P link and the secondary UE to operate at higher order MIMO. FIG. 3Billustrates an example environment in which a pair of UEs can enablecommunication with one or more additional TRPs to increase rank of MIMOcommunication between the network and the primary UE.

FIG. 1 is a diagram illustrating a multiple-input multiple-output (MIMO)network in which user equipment (UE) and a network system wirelesslycommunicate according to an embodiment. FIG. 1 shows an exampleenvironment 100 for MIMO wireless communications. Various UEs cancommunicate with a network system via MIMO communications in theenvironment 100. Certain UEs of the environment 100 can form a clonepair to increase the data rate and/or MIMO rank of exchanging MIMO dataassociated with one UE.

Various standards and protocols may be implemented in the environment100 to wirelessly communicate data between a base station and a wirelesscommunication device. Some wireless devices may communicate using anorthogonal frequency-division multiplexing (OFDM) digital modulationscheme via a physical layer. Example standards and protocols forwireless communication in the environment 100 can include the thirdgeneration partnership project (3GPP) Long Term Evolution (LTE), LongTerm Evolution Advanced (LTE Advanced), 3GPP New Radio (NR) also knownas 5G, Global System for Mobile Communications (GSM), Enhanced DataRates for GSM Evolution (EDGE), Worldwide Interoperability for MicrowaveAccess (WiMAX), and the IEEE 802.11 standard, which may be known asWi-Fi. In some systems, a radio access network (RAN) may include one ormore base station associated with one or more evolved Node Bs (alsocommonly denoted as enhanced Node Bs, eNodeBs, or eNBs, gNBs, or anyother suitable Node Bs (xNBs)). In some other embodiments, radio networkcontrollers (RNCs) may be provided as the base stations. A base stationprovides a bridge between the wireless network and a core network suchas the Internet. The base station may be included to facilitate exchangeof data for the wireless communication devices of the wireless network.

A wireless communication device may be referred to a user equipment(UE). The UE may be a device used by a user such as a smartphone, alaptop, a tablet computer, cellular telephone, a wearable computingdevice such as smart glasses or a smart watch or an ear piece, one ormore networked appliances (e.g., consumer networked appliances orindustrial plant equipment), an industrial robot with connectivity, or avehicle. In some implementations, the UE may include a sensor or othernetworked device configured to collect data and wirelessly provide thedata to a device (e.g., server) connected to a core network such as theInternet. Such devices may be referred to as Internet of Things devices(IoT devices). Any suitable UE disclosed herein can be part of a clonepair. A downlink (DL) transmission generally refers to a communicationfrom the base transceiver station (BTS) or eNodeB to the wirelesscommunication device, and an uplink (UL) transmission generally refersto a communication from the wireless communication device to the BTS.

FIG. 1 illustrates a cooperative, or cloud radio access network (C-RAN)environment 100. In the environment 100, the eNodeB functionality issubdivided between a base band unit (BBU) 110 and multiple remote radiounits (RRUs) (e.g., RRU 125, RRU 135, and RRU 145). The network systemof FIG. 1 includes the BBU 110 and the RRUs 125, 135, and 145. An RRUmay include multiple antennas, and one or more of the antennas may serveas a transmit-receive point (TRP). The RRU and/or a TRP may be referredto as a serving node. The BBU 110 may be physically connected to theRRUs such as via an optical fiber connection. The BBU 110 may provideoperational information to an RRU to control transmission and receptionof signals from the RRU along with control data and payload data totransmit. The RRU may provide data to the network received from UEswithin a service area associated with the RRU. As shown in FIG. 1, theRRU 125 provides service to devices within a service area 120. The RRU135 provides service to devices within a service area 130. The RRU 145provides service to devices within a service area 140. For example,wireless downlink transmission service may be provided to the servicearea 140 to communicate date to one or more devices within the servicearea 140.

The illustrated RRUs 125, 135, and 145 include multiple antennas and canprovide MIMO communications. For example, an RRU may be equipped withvarious numbers of transmit antennas (e.g., 2, 4, 8, or more) that canbe used simultaneously for transmission to one or more receivers, suchas a UE. Receiving devices may include more than one receive antenna(e.g., 2, 4, etc.). An array of receive antennas may be configured tosimultaneously receive transmissions from the RRU. Each antenna includedin an RRU may be individually configured to transmit and/or receiveaccording to a specific time, frequency, power, and directionconfiguration. Similarly, each antenna included in a UE may beindividually configured to transmit or receive according to a specifictime, frequency, power, and direction configuration. The configurationmay be provided by the BBU 110. The direction configuration may begenerated based on a network estimate using channel reciprocity and/ordetermined based on feedback from UE via selection of a beamformingcodebook index, or a hybrid of the two.

The service areas shown in FIG. 1 may provide communication services toa heterogeneous population of user equipment. For example, the servicearea 120 may include a cluster of UEs 160 such as a group of devicesassociated with users attending a large event. The service area 120 canalso include an additional UE 162 that is located away from the clusterof UEs 160. A mobile user equipment 170 may move from the service area130 to the service area 140. Another example of a mobile user equipmentis a vehicle 156 which may include a transceiver for wirelesscommunications for real-time navigation, on-board data services (e.g.,streaming video or audio), or other data applications. The environment100 may include semi-mobile or stationary UEs, such as robotic device158 (e.g., robotic arm, autonomous drive unit, or other industrial orcommercial robot) or a television 154, configured for wirelesscommunications.

A user equipment 152 may be located with an area with overlappingservice (e.g., the service area 120 and the service area 130). Eachdevice in the environment 100 may have different performance needs whichmay, in some instances, conflict with the needs of other devices.

Clone pairs can be formed in the environment 100. For example, there canbe more MIMO dimensions from the RRU 125 available to the UE 162 thanthe UE 162 can process acting alone in certain instances. In such acase, the UE 162 can form a clone pair with the UE 152 to jointlycommunicate with the RRU 125 in a manner that uses more MIMO dimensionsthan the UE 162 would alone. As another example, the TRPs of the RRU 125can be limited for serving the cluster of UEs 160 and the UE 162 in someinstances. In such a case, the UE 162 can form a clone pair with the UE152 and also exchange data associated with the UE 162 with one or moreTRPs of the RRU 135. This can enable more TRPs to serve the UE 162 thancompared to the UE 162 communicating with the network system alone.

Increasing Rank and/or Data Rate with a Pair of UEs

In various MIMO network environments, a relatively large number of TRPsare available for communicating with UEs. A UE peak data rate can belimited by a antennas and/or streams of the UE in certain instances. Forexample, a UE with 2 receive antennas and 2 transmit antennas can havean uplink peak rate limited by rank 2 and a downlink peak rate limitedby rank 2. With a relatively large number of TRPs available, a networksystem can have excess capacity to serve the UE. Aspects of thisdisclosure relate to establishing a P2P link between two UEs and usingthe reception and/or transmission capabilities of the two UEs toincrease the data rate and/or rank associated with one of the UEs. Afirst UE and a second UE can both wirelessly communicate data associatedwith the first UE via cellular links. The first UE and the second UE canalso communicate with each other via a P2P link while the first UE andthe second UE are communicating with a network system via cellularlinks.

FIG. 2A is a diagram illustrating coordinated transmission and receptionof MIMO data for one UE by two UEs communicating via a P2P linkaccording to an embodiment. FIG. 2A illustrates an example of a clonepair enabling a larger number of TRPs to serve a primary UE to therebyincrease a data rate and MIMO rank associated with the primary UE.

The example MIMO wireless communication environment 200 of FIG. 2Aincludes a BBU 110, a RRU 202 with a plurality of TRPs 204, a primary UE210, and a secondary UE 220. The RRU 202 can be implemented bydistributed RRUs in certain applications. The TRPs 204 can bedistributed in certain applications. The illustrated primary UE 210includes receive antennas 212, transmit antennas 214, and an antenna218. The illustrated receive antennas 212 can receive downlink MIMO datawith rank 2. The illustrated transmit antennas 214 can transmit uplinkMIMO data with rank 2. The illustrated secondary UE 220 includes receiveantennas 222, transmit antennas 224, and an antenna 228. The illustratedreceive antennas 222 can receive downlink MIMO data with rank 2. Theillustrated transmit antennas 224 can transmit uplink MIMO data withrank 2. A P2P link can be established using the antennas 218 and 228. Invarious applications, the primary UE 210 and the secondary UE 220 canhave different numbers of antennas.

There are a large number of TRPs 204 relative to the number of antennasof the UEs in the environment 200. Accordingly, the communication rateof the primary UE 210 can be limited by the antennas and/or signalchains of the primary UE 210 when the primary UE 210 is in communicationwith the TRPs 204 by itself. In such a case, the TRPs 204 have excesscapacity to serve the primary UE 210.

The primary UE 210 can establish a P2P link with the secondary UE 220.The P2P link can be used to exchange traffic between the primary UE 210and the secondary UE 220. The P2P link can be a Wi-Fi link, a Bluetoothlink, a cellular link, or the like. P2P communications can beout-of-band. P2P communications can be in-band in some cases. The P2Plink can enable relatively fast data transfer between the primary UE 210and the secondary UE 220. In some instances, the secondary UE 220 canprocess the second part of the MIMO data associated with the primary UE210 and send the processed data to the primary UE 210 via the P2P link.The data provided over the P2P link can be samples (modulation), bits(physical layer), or bytes (higher layer). The primary UE 210 and thesecondary UE 220 can together coordinate transmission and reception ofMIMO data associated with the primary UE 210.

Downlink MIMO data associated with the primary UE 210 can be received bythe primary UE 210 and the secondary UE 220. A first part of the MIMOdata associated with the primary UE 210 can be received by the primaryUE 210. A second part of the MIMO data associated with the primary UE210 can be received by the secondary UE 220. The secondary UE 220 canprovide the second part of the MIMO data associated with the primary UE210 to the primary UE 210 via the P2P link. In the example illustratedin FIG. 2A, the primary UE 210 and the secondary UE 220 can each receivedownlink MIMO data with a rank of two. By transferring the second partof the MIMO data associated with the primary UE 210 to the primary UE210 via the P2P link, the primary UE 210 can receive downlink MIMO datawith a rank of 4. Similarly, by transferring the second part of the MIMOdata associated with the primary UE 210 to the primary UE 210 via theP2P link, the primary UE 210 can receive downlink MIMO data at about 2times the maximum data rate corresponding to receiving downlink MIMOdata by the antennas 212. The primary UE 210 can process the first partof the MIMO data together with the second part of the MIMO data.

A realization is to mutually exchange information over the P2P link, andeach of the primary and second UE's could process 2 of the 4 MIMOlayers, with the final decode data transported back to the primary UE.This approach can share the received antenna information and also sharethe computational processing between the primary and secondary UE's,which can together form a distributed realization of the virtual UE ofhigher MIMO capability.

Uplink MIMO data associated with the primary UE 210 can be transmittedby the primary UE 210 and the secondary UE 220. A processor of theprimary UE 210 can cause transmission of a first part of a MIMO uplinkdata transmission via the antennas 214 and to cause transmission of asecond part of the MIMO uplink data transmission to the secondary UE 220via the peer-to-peer link. The secondary UE 220 can then transmit thesecond part of the uplink MIMO data transmission via the antennas 224.In the example illustrated in FIG. 2A, the primary UE 210 and thesecondary UE 220 can each transmit uplink MIMO data with a rank of two.By sending the second part of the MIMO data associated with the primaryUE 210 to the primary UE 210 via the P2P link, uplink MIMO dataassociated with the primary UE 210 can be effectively transmitted with arank of 4. Similarly, by sending the second part of the MIMO dataassociated with the primary UE 210 to the secondary UE 210 via the P2Plink and having the secondary UE 220 transmit the second part of theMIMO data to the network system, uplink MIMO data associated with theprimary UE 210 can be effectively transmitted at about 2 times themaximum data rate corresponding to transmitting uplink MIMO data by theantennas 214.

Although the environment 200 of FIG. 2A illustrates using paired UEs totransmit and receive MIMO data, any suitable principles and advantagesdisclosed herein can be applied to cases where there are unbalanceduplink and downlink wireless communications. For example, downlink datafor a primary UE can be received by paired UEs and uplink data for theprimary UE can be transmitted to a network system by a single UE only.The MIMO wireless communication environment 200′ of FIG. 2B illustratesan example of such a case. The single UE can be the primary UE asillustrated in FIG. 2B. In some instances, the single UE can be thesecondary UE. As another example, uplink data for a primary UE can betransmitted to a network system by paired UEs and downlink data for theprimary UE can be received from the network system by a single UE. TheMIMO wireless communication environment 200″ of FIG. 2C illustrates anexample of such a case. The single UE receiving downlink data can be theprimary UE as shown in FIG. 2C. In some instances, the single UE can bethe secondary UE. As one more example, uplink MIMO transmissionsassociated with a primary UE can be transmitted by paired UEs anddownlink MIMO transmissions associated with the primary UE can bereceived by the paired UEs, in which the uplink and downlink MIMOtransmissions have different rank.

FIG. 2B is a diagram illustrating coordinated reception of MIMO data forone UE by two UEs communicating via a P2P link according to anembodiment. FIG. 2B illustrates an example of a clone pair enabling alarger number of TRPs to serve downlink data to a primary UE to therebyincrease a downlink data rate and MIMO rank associated with the primaryUE. The MIMO wireless communication environment 200′ is in a differentstate than the MIMO wireless communication environment 200 of FIG. 2A.In FIG. 2B, the secondary UE 220 receives MIMO downlink data for theprimary UE 210 from the RRU 202. However, the secondary UE 220 does nottransmit uplink data for the primary UE 210 to the RRU 202 in the stateshown in FIG. 2B. As illustrated, the network system receives uplinkdata associated with the primary UE 210 from a single UE via cellularcommunications. In FIG. 2B, the single UE is the primary UE 210.

FIG. 2C is a diagram illustrating coordinated transmission of MIMO datafor one UE by two UEs communicating via a P2P link according to anembodiment. FIG. 2C illustrates an example of a clone pair enabling alarger number of transmit antennas to transmit uplink data associatedwith a primary UE to thereby increase an uplink data rate and MIMO rankassociated with the primary UE. The MIMO wireless communicationenvironment 200″ is in a different state than the MIMO wirelesscommunication environment 200 of FIG. 2A. In FIG. 2C, the secondary UE220 transmits MIMO uplink data for the primary UE 210 to the RRU 202.However, the secondary UE 220 does not receive uplink data for theprimary UE 210 from the RRU 202 in the state shown in FIG. 2C. Asillustrated, the network system transmits downlink data associated withthe primary UE 210 to a single UE via cellular communications. In FIG.2C, the single UE is the primary UE 210.

Embodiments disclosed herein relate to utilizing one or more additionaltransmit antennas to increase the MIMO rank of a wireless transmission.An alternative approach according to an embodiment is to maintain thesame MIMO rank and enable transmit diversity for paired UEs wirelesslycommunicating with a network system. Accordingly, a secondary UE canprovide transmit diversity. Transmit diversity can be, for example, suchas described in LTE or another wireless communication standard. Thetransmit diversity can increase the supported data rate. Examples oftransmit diversity include single-frequency network (SFN) modulation andAlamouti space-time block coding (STBC).

The principles and advantages of transmission and/or reception of MIMOdata can be applied to other examples beyond the examples shown in FIGS.2A to 2C. For example, the primary UE 210 and the secondary UE 220 canhave different numbers of antennas and/or different transmit and/orreceive capabilities. Data communication rates between the primary UE210 and the network system can increase in such cases by a differentamount and/or by a different rank by using a secondary UE fortransmission and/or reception of MIMO data associated with the primaryUE 210 compared to the examples of FIGS. 2A to 2C. In some instances, aprimary UE can include a single antenna to transmit data to the networksystem and transmit MIMO data and using the single transmit antenna ofthe primary UE and one or more transmit antennas of a secondary UE incommunication with the primary UE via a P2P link. Alternatively oradditionally, a primary UE can include a single antenna to receive datafrom the network system and receive MIMO data and using the singlereceive antenna of the primary UE and one or more receive antennas of asecondary UE in communication with the primary UE via a P2P link.

FIG. 3A is a diagram illustrating a MIMO network in which datatransmission and reception associated with a primary UE is limited bythe number of TRPs for serving the primary UE. FIG. 3A illustrates a usecase that can benefit from technology described herein.

The example MIMO wireless communication environment 300 of FIG. 3Aincludes a BBU 110, a first RRU 302, a second RRU 304, clustered UEs310, a first UE 320, and a second UE 330. As illustrated, the clusteredUEs 310 are located around TRPs of the first RRU 302. Accordingly, thenumber of TRPs of the first RRU 302 can be limited for serving theclustered UEs 310 and the first UE 320. In such circumstances, the TRPsof the first RRU 302 can limit the data rate and/or rank of wirelesscommunication between the first UE 320 and the first RRU 302. There aremore TRPs in network system available to serve the first UE 320 that areunutilized. For example, the TRPs of the second RRU 304 are unutilizedas shown in FIG. 3A. In the environment 300, the second UE 330 is idle.

FIG. 3B is a diagram illustrating the first UE 320 of FIG. 3A with a P2Plink with the second UE 330 to enable the first UE 320 to receive MIMOdata with a higher rank than in the case of FIG. 3A. FIG. 3B illustratesan example MIMO wireless communication environment 300′ in a differentstate than the MIMO wireless communication environment 300 of FIG. 3A.In FIG. 3B, the first UE 320 functions as a primary UE and the second UE330 functions as a secondary UE. As illustrated, there is a first pathp1 from the BBU 110 to the first UE 320 via the first RRU 302. There isalso a second path p2 from the BBU 110 to the first UE 320 via thesecond RRU 304 and the second UE 330. The state in FIG. 3B enables thefirst UE 320 and the network system to exchange MIMO data at a higherrate and/or higher MIMO rank than the state of FIG. 3A.

In the environment 300′, the previously idle second UE 330 is used as arelay point for the first UE 320. The first UE 320 can establish a P2Plink with the second UE 330 and communicate with the second RRU 304 viathe P2P link and the second UE 330. The P2P link can enable spatialdiversity. This can enable TRPs of the second RRU 304 to serve the firstUE 320. The secondary UE 320 can enable a network system to operate athigher-order MU-MIMO. For example, when the first UE 320 and second UE330 are similar devices, the rank of MIMO communication between thefirst UE 320 and the network system can be doubled. The actual MIMOorder increase can depend on one or more spatial channel conditionsand/or capabilities of the second UE 330 and/or the first UE 320.

The principles and advantages disclosed with reference to FIG. 3B can beapplied to contexts where there in unbalanced traffic. For example,downlink data for the primary UE 320 can be received by paired UEs 320and 330 and uplink data for the primary UE 320 can be transmitted to thenetwork system by the primary UE 320 only. As another example, uplinkdata for the primary UE 320 can be transmitted to the network system bypaired UEs 320 and 330 and downlink data for the primary UE 320 can bereceived from the network system by the primary UE 320 only. As one moreexample, uplink MIMO transmissions associated with the primary UE 320can be transmitted by paired UEs 320 and 330 and downlink MIMOtransmissions associated with the primary UE 320 can be received by thepaired UEs 320 and 330, in which the uplink and downlink MIMOtransmissions have different rank.

Network System

FIG. 4 is a block diagram illustrating an example network system 400that includes base band unit 402 and remote radio units 490 according toan embodiment. The network system 400 of FIG. 4 can wirelesslycommunicate with UEs in accordance with any suitable principles andadvantages disclosed herein.

The base band unit 402 can be coupled with at least one remote radiounit 490. The base band unit 402 can be coupled with a plurality ofremote radio units 490. Such remote radio units 490 can be distributed.A remote radio unit 490 can include at least a first antenna 496 and asecond antenna 498 for MIMO wireless communications. Any antennadisclosed herein, such as the antenna 496 or the antenna 498, can bereferred to as antenna element. A remote radio unit can include anysuitable number of antennas and/or arrays of antennas. The antennas 496and 498 of the RRU 490 can be coupled with a radio frequency (RF) frontend 494. The RF front end 494 can process signals received via theantennas 496 and/or 498. Part of processing a signal may includeproviding the signal to a transceiver 420 included in the BBU 402. TheRF front end 494 can process signals provided by the transceiver 420 fortransmission via the antennas 496 and/or 498.

As illustrated, the BBU 402 includes a processor 405, a data store 410,a beamformer 415, a transceiver 420, and a bus 480. The bus 480 cancouple several elements of the BBU 402. The illustrated processor 405includes a network monitor 425, a peer pairing engine 430, and a peerdata processor 435.

The processor 405 can include any suitable physical hardware configuredto perform the functionality described with reference to the processor405 and elements thereof. The processor 405 can include a processorconfigured with specific executable instructions, a microprocessor, amicrocontroller, a digital signal processor (DSP), an applicationspecific integrated circuit (ASIC), a programmable logic device such asfield programmable gate array (FPGA), the like, or any combinationthereof designed to perform the functions described herein. Theprocessor 405 can be implemented by any suitable combination ofcomputing devices and/or discrete processing circuits in certainapplications.

The network monitor 425 can detect one or more characteristics of thenetwork such as areas where TRPs of the network system have excesscapacity, areas that are relatively heavily loaded, or the like. Thepeer pairing engine 430 can receive network characteristic data from thenetwork monitor 425 and use the network characteristic data indetermining a clone pair. The network monitor 425 can be implemented bydedicated circuitry of the processor 405 and/or by circuitry of theprocessor 405 that can be used for other functionality.

In certain instances, the network system can pair a primary UE and asecondary UE for coordinated reception and transmission of MIMO dataassociated with the primary UE. The peer pairing engine 430 can pair theprimary UE with the secondary UE in some applications. In response todetermining a clone pair, the peer pairing engine 430 can send a clonepairing command to primary UE and/or secondary UE to initiate a clonepair. The peer pairing engine 430 can be implemented by dedicatedcircuitry of the processor 405 and/or by circuitry of the processor 405that can be used for other functionality.

The pairing determination can be based on pairing informationtransmitted by the primary UE and/or the secondary UE to the networksystem. The peer pairing engine 430 can determine a clone pair based onjoint spectral efficiency of a pair of UEs. The joint spectralefficiency can be transmitted to the network system by a primary UE. Insome instances, the peer pairing engine can compute joint spectralefficiency for a pair of UEs based on information received from each UEof the pair.

The BBU 402 can receive information from a plurality of UEs and takeinto account more information than available to a single UE or a pair ofUEs in determining a clone pair. Accordingly, the peer pairing engine430 can take into account pairing information received from a primary UEand/or secondary UE and additional network information in determiningthe clone pair. The additional network information can include, forexample, one or more of mobility state information for one or more UEs,spatial channel state conditions for one or more UEs, system loadinformation, characteristics of one or more UEs (e.g., a traffic state,an amount of battery life, or a device type), information associatedwith available TRPs associated with one or more of the UEs, the like, orany suitable combination thereof.

In another mode of operation, the peer pairing engine 430 can decidewhether to grant a tunnel request from a primary UE to setup a tunnelbetween the primary UE and the network system that goes through thesecondary UE. In response to granting such a request, the network systemcan set up a tunnel through the secondary UE to the primary UE, forexample, based on a dual connectivity protocol.

The peer data processor 435 of the BBU 402 can process and/or aggregateMIMO data associated with a primary UE for coordinated communicationwith a clone pair. For example, the peer data processor 435 can receivedownlink MIMO data for a primary UE, cause a first part of the downlinkdata for the primary UE to be transmitted to the primary UE, and cause asecond part of the downlink data for the primary UE to be transmitted toa secondary UE, in which the secondary UE has a P2P link establishedwith the primary UE. This can enable the primary UE to receive thedownlink MIMO data with higher rank and/or at a higher data rate.

As another example, the peer data processor 435 can receive a first partof uplink MIMO data associated with a primary UE from the primary UE,receive a second part of uplink MIMO data associated with the primary UEfrom a secondary UE, and jointly process and/or combine the first partand the second part of the MIMO data associated with the primary UE.

The peer data processor 435 can be implemented by dedicated circuitry ofthe processor 405 and/or by circuitry of the processor 405 that can beused for other functionality.

As illustrated, the processor 405 is in communication the data store410. The data store 410 include instructions that can be executed by theprocessor 405 to implement any suitable combination of the featuresdescribed herein. In some implementations, the data store 410 can retainchannel information for UEs served by the BBU 402. The data store 410may be indexed by UE identifier and/or RRU identifier. This can expediteidentification of previously communicated scheduling information for theUE and for monitoring network conditions (e.g., number of UEs allocatedto an RRU or antenna element of an RRU).

The beamformer 415 can generate parameters for the serving nodes (e.g.,RRUs) for a primary UE and a secondary UE. The parameters can includeone or more of transmission mode, time, frequency, power, beamformingmatrix, tone allocation, or channel rank. The beamformer 415 candetermine optimal parameters for RRUs 490 coupled with the BBU 402 thatfacilitate a network-wide optimization of downlink data transmissions.Similar functionality can be implemented for receiving uplink datatransmission.

The illustrated processor 405 is in communication the transceiver 420.The transceiver 420 includes a receiver and a transmitter. The receivercan process signals received from the RF front end 494. The transmittercan provide signals to the RF front end 494 for transmission via one ormore antennas 496 and/or 498.

User Equipment

A variety of different UEs can be part of a clone pair. Such UEs caninclude any suitable UE disclosed herein. Certain UEs can function aseither a primary UE or a secondary UE. Some UEs can only function as aprimary UE of a clone pair. Various UEs can only function as a secondaryUE of a clone pair. As example UE that can function as either a primaryUE or a secondary UE of a clone pair will be discussed with reference toFIG. 5.

FIG. 5 is a schematic block diagram of an example UE 500 according to anembodiment. The UE 500 is configured for wirelessly communicating with abase station and also wirelessly communicating with another UE via a P2Plink. The UE 500 can function as a primary UE. The UE 500 can functionas a secondary UE. As illustrated, the UE 500 includes a processor 505that includes a peer selector 506 and a peer communications processor508, a data store 510, a user interface 515, a beamformer 525, a signalquality analyzer 530, a peer-to-peer transceiver 540, a peer-to-peerradio frequency front end 545, an antenna 548 for peer-to-peercommunications, a transceiver 550, a radio frequency front end 555, andantennas 562 and 564. In some instances, the UE 500 can include amicrophone and a speaker (not illustrated). Some other UEs can includeadditional elements and/or a subset of the elements illustrated in FIG.5.

The UE 500 includes circuitry for cellular communications. Thetransceiver 550 and the radio frequency front end 555 can generatesignals for uplink cellular data transmissions via the antennas 562 and564. The transceiver 550 includes a transmitter and a receiver. Thetransmitter can include one or more transmit chains. In certaininstances, the transmitter includes a plurality of transmit chains. Thenumber of transmit chains can set a maximum uplink data rate and/or rankfor MIMO data transmitted by the antennas of the UE 500 to a networksystem. In certain instances, the number of antennas available forwirelessly transmitting uplink data to the network system can set amaximum uplink data rate and/or rank for MIMO data transmitted by theantennas of the UE 500 to a network system

The transceiver 550 and the radio frequency front end 555 can processdownlink cellular data transmissions received via the antennas 562 and564. The receiver of transceiver 550 can include one or more receivechains. In certain instances, receiver can include a plurality ofreceive chains. The number of receive channels can limit maximumdownlink data rate and/or rank for MIMO data received by the antennas ofthe UE 500 from a network system. In certain instances, the number ofantennas available for wirelessly receiving downlink data from thenetwork system can set a maximum downlink data rate and/or rank for MIMOdata received by the antennas of the UE 500 from the network system.

The UE 500 can include any suitable number of antennas for wirelesslycommunicating with a network system. The antennas of the UE 500 caninclude one or more receive only antennas and/or one or more transmitonly antennas. The antennas of the UE 500 can include one or moretransmit and receive antennas configured to transmit and receivewireless data.

The UE 500 includes circuitry for peer-to-peer wireless communicationswith another UE. The peer-to-peer wireless communications can be over anon-cellular communication channel. A peer-to-peer wireless interfacecan refer to circuitry of the UE 500 configured to wirelesslycommunicate (e.g., receive and/or transmit) data to another UE via apeer-to-peer communication channel. As shown in FIG. 5, the UE 500includes a peer-to-peer wireless interface 546. The peer-to-peerwireless interface 546 includes a peer-to-peer transceiver 540 and apeer-to-peer radio frequency front end 545. The peer-to-peer transceiver540 and the peer-to-peer radio frequency front end 545 cause data to betransmitted over the peer-to-peer link via the antenna 548. Thepeer-to-peer transceiver 540 and the peer-to-peer radio frequency frontend 545 can process data received over the peer-to-peer link via theantenna 548. The UE 500 can be configured to transmit and/or receiveMIMO physical layer information over the peer-to-peer link in certainapplications. Symbol level data can be exchanged over the peer-to-peerlink in various applications.

The wireless signals exchanged over the peer-to-peer link can benon-cellular wireless signals. The non-cellular wireless signals can bein accordance with a wireless local area network (WLAN) standard or awireless personal area network (WPAN) standard. The non-cellularwireless signals can be Bluetooth signals, Wi-Fi signals, ZigBeesignals, or the like. The non-cellular wireless signals can have ashorter signal range than cellular signals. In some instances, thenon-cellular wireless signals can have a range of about 300 feet orless. The non-cellular wireless signals can have a range of about 150feet or less in certain applications. The non-cellular wireless signalscan have a range of about 35 feet or less in some other applications. Insome instances, the wireless signals exchanged over the peer-to-peerlink can be cellular signals.

The processor 505 can include any suitable physical hardware configuredto perform the functionality described with reference to the processor505 and elements thereof. The processor 505 can include a processorconfigured with specific executable instructions, a microprocessor, amicrocontroller, a digital signal processor (DSP), an applicationspecific integrated circuit (ASIC), a programmable logic device such asfield programmable gate array (FPGA), the like, or any combinationthereof designed to perform the functions described herein. Theprocessor 505 can be implemented by any suitable combination ofcomputing devices and/or discrete processing circuits in certainapplications. The peer selector 506 can be implemented by dedicatedcircuitry of the processor 505 and/or by circuitry of the processor 505that can be used for other functionality. The peer communicationsprocessor 508 can be implemented by dedicated circuitry of the processor505 and/or by circuitry of the processor 505 that can be used for otherfunctionality.

In certain instances, the UE 500 can initiate a clone pair. The UE 500can function as a primary UE in certain instances. The peer selector 506can perform functions related to selecting a secondary UE for a clonepair with UE 500 serving as a primary UE. For example, the peer selector506 can cause the UE 500 to discover one or more candidate secondary UEsfor a clone pair. The peer selector 506 can execute functionalityassociated with one or more of collecting data from one or morecandidate secondary UEs, determining joint spectral efficiency ofpossible clone pairs, or prioritizing secondary UEs. The peer selector506 can send pairing information to a network system for making apairing decision in certain applications. In some other instances, thepeer selector 506 can make a pairing decision and initiate a clone pair.Examples of such functionalities of the peer selector 506 are discussedwith reference to FIGS. 6 to 8.

As discussed above, the UE 500 can function as a secondary UE of a clonepair. The peer selector 506 can perform functionality associated withthe UE 500 deciding whether to function as a secondary UE of a clonepair. For example, the peer selector 506 can accept or reject a requestfor the UE 500 to function as a secondary UE for a primary UE. The peerselector 506 can make this determination based on one or more of avariety of factors, such as battery life, traffic state, incentives,etc. The peer selector 506 can also initiate a confirmation or rejectionof a clone pair request to be send to a primary UE. Examples of suchfunctionalities of the peer selector 506 are discussed with reference toFIGS. 6 to 8.

The peer communications processor 508 can jointly process and/oraggregate MIMO data associated with the UE 500 when the UE 500 isoperating as a primary UE of a clone pair. The peer communicationsprocessor 508 can jointly process and/or aggregate downlink datareceived via the antennas 562, 564, and 548. The peer communicationsprocessor 508 can jointly process uplink data for transmission via theantennas 562, 564, and 548. The peer communications processor 508 canestablish a peer-to-peer link with another UE.

The peer communications processor 508 can perform operations associatedwith processing and transmitting MIMO data associated with another UEwhen the UE 500 is operating as a secondary UE of a clone pair. The peercommunications processor 508 can cause the UE 508 to enter a clone modeto operate as a secondary UE. The peer communications processor 508 candetect that received data is associated with a primary UE. In certainapplications, the peer communications processor 508 can generate symbollevel data from MIMO data received from a network system, and the causethe symbol level data to be transmitted to a primary UE via thepeer-to-peer link. The peer communications processor 508 can cause MIMOphysical layer data to be transmitted to primary UE via the peer-to-peerlink. MIMO physical layer data can include data from, for example, highdefinition video streaming, a relatively large content download, or asocial network content sharing application. The peer communicationsprocessor 508 can manage communications with another UE over thepeer-to-peer link. Examples of functionalities of the peercommunications processor 508 are discussed with reference to FIGS. 6 to8.

The processor 505 can be in communication with the signal qualityanalyzer 530. The signal quality analyzer 530 can analyze the quality ofsignals received and/or transmitted by any of the antennas of the UE500. This can provide information associated with a spatial channelcondition of the UE 500. This information can be provided to theprocessor 505 for determining one or more of a spectral efficiency ofthe UE 500, an estimated joint spectral efficiency of the UE 500 andanother UE, or a relative priority of other UEs as candidate secondaryUEs. In some instances, some or all of the functionality of the signalquality analyzer can be implemented by the processor 505.

The beamformer 525 can perform any suitable beamforming functionalityfor the UE 500. The beamformer 525 can set and/or adjust one or moreparameters associated with receiving and/or transmitting signalsassociated with the antennas 562 and 564 of the UE 500. The beamformer525 can be implemented by dedicated circuitry and/or circuitry of theprocessor 505.

The UE 500 includes a data store 510. The data store 510 can storeinstructions that can be executed by the processor 505 to implement anysuitable features described herein. The data store 510 can dataassociated with candidate secondary UEs, such as joint spectralefficiency data. When the UE 500 functions as a secondary UE, the datastore 510 can store an identifier of the primary UE. The identifier ofthe primary UE can be used by the UE 500 in functioning as a secondaryUE. When the UE 500 functions as a secondary UE, the data store 510 canstore any other suitable information about a paired primary UE, such asinformation about MIMO capabilities and/or number of antennas. The datastore 510 can store any other suitable data for the UE 500. The datastore 510 can include any suitable memory elements arranged to storedata.

As illustrated, the UE 500 also includes a user interface 515. The userinterface 515 can be any suitable user interface, such as a displayand/or an audio component. In some instances, the user interface 515 caninclude one or more of touch screen capabilities, a button, a knob, aswitch, or a slider.

Several elements included in the UE 500 may be coupled by a bus 580. Thebus 580 can be a data bus, communication bus, other bus, or any suitablecombination thereof to enable the various components of the UE 1200 toexchange information.

Tightly Coupled Mode

A pair of UEs can perform coordinated transmission and/or reception ofMIMO data associated with one UE of the pair either as a tightly coupledpair of UEs or as a loosely coupled pair of UEs. In a tightly coupledpair of UEs, the primary UE and the secondary UE can share an identityfrom a network perspective. A base station can serve the primary UE andthe secondary UE with a single-user MIMO operation in the tightlycoupled mode. The secondary UE can send processed data to the primary UEvia a P2P link for aggregation on the primary UE. Aggregation of MIMOdata can be at the physical layer or a higher layer. Data received atthe primary UE and secondary UE can also be jointly processed viainformation shared over the P2P link. Example operations for tightlycoupled UE pairs are discussed with reference to FIGS. 6 and 7.

In a tightly coupled mode, the secondary UE can store informationassociated with the primary UE in memory, such as an identifier of theprimary UE and/or information associated with MIMO capabilities of theprimary UE (e.g., a number of antennas). Such information can beprovided to the secondary UE from the primary UE via a P2P link.Alternatively or additionally, a network system can provide suchinformation associated with the primary UE to the secondary UE in thetightly coupled mode. The secondary UE can provide MIMO physical layerinformation to the primary UE via a P2P link in the tightly coupledmode. Example MIMO physical layer information that the secondary UE canprovide to the primary UE over a P2P link includes one or more of rank,preferred precoding information, or a channel estimate.

For a tightly coupled mode, a clone pair can be initiated while theprimary UE is in a traffic state. The primary UE may determine todissociate the P2P link with the secondary UE in response to detectingchannel degradation of the secondary UE. The primary UE may determine todissociate the P2P link with the secondary UE in response to detecting achange in state of the secondary UE (e.g., a traffic state change, lowbattery mode, etc.). The primary UE can return from clone mode to asingle user mode prior to a clone-haul disassociation.

Clone paring candidate consideration in a tightly coupled mode can bebased on a UE based discovery based on P2P beacon measurement. A clonepair candidate in an idle state can be preferred over another clone paircandidate in an active state. In some instances, a secondary UE can bein an active state and be part of a clone pair. Network assisteddiscovery with a list of available idle secondary UEs can beimplemented. A clone pair association only to UEs in communication withthe same BBU and/or cell, but that can be in communication withdifferent TRPs within the same BBU and/or cell can be implemented.

FIG. 6 illustrates example communications and events of an embodiment ofestablishing a clone pair of UEs and jointly receiving MIMO dataassociated with one UE of the clone pair using both UEs of the clonepair. The communications and events of FIG. 6 relate to a tightlycoupled mode in which a primary UE 610 and a secondary UE 620 share anidentity as a clone pair. In the communications and events of FIG. 6,the clone pair decision is UE centric. The message flow 600 illustratesexample communications and events associated with a primary userequipment 610, a secondary user equipment 620, and a network system 630.The primary UE 610 can implement any suitable features of the UEsdisclosed herein. The secondary UE 620 can implement any suitablefeatures of the UEs disclosed herein. The network system 630 may includea base band unit or other network device configured to schedulecommunications with devices within a service area. The network system630 can also include a plurality of RRUs and/or TRPs. Additional oralternative entities may be included to mediate one or more of theinteractions shown such as network routers, switches, security devices,or the like.

In event 640, the primary UE 610 can discover the secondary UE 620. Thediscovery may include receiving, at the primary UE 610 a message fromthe secondary UE 620. In some implementations, the discovery may be abroadcast discovery whereby a message is generally transmitted todevices within a range of the primary UE 610. The discovery may includepeer-to-peer beacons and/or signals. The message may include informationindicating clone pairing capabilities. In such instances, devices thatcan perform clone pairing may respond. Although shown as discovering asingle secondary UE in FIG. 6, the primary UE 610 may discover two ormore secondary UEs with which it could establish a clone pairing. Thesecondary UE 620 may be within the same cell as the primary UE 610. Insome instances, the secondary UE 620 and the primary UE 610 can beserved by different TRPs within the same cell.

The primary UE 610 can collect information associated with the secondaryUE 620. For example, the primary UE 610 can collect one or more ofavailability of the secondary UE 620 to serve as a secondary UE for theprimary UE 610, recent channel quality indicator (CQI) information,precoding selection, or the like. The primary UE 610 can store thecollected information associated with the secondary UE 620. The primaryUE 610 can collect and store information associated with a plurality ofsecondary UEs 620.

After discovering the secondary UE 620, the primary UE 610 may generatepairing information at event 642. The primary UE 610 can compute a jointspectral efficiency of the primary UE 610 and the secondary UE 620operating as a clone pair. The computation of spectral efficiency can bebased on information collected associated with discovering the secondaryUE in event 640. For example, the joint spectral efficiency can be basedon cellular channel information for the secondary UE 620, informationabout the P2P link, and cellular channel information for the primary UE610. The UE pairing information can include the joint spectralefficiency. The joint spectral efficiency and/or other pairinginformation can be computed for one or more additional secondary UEs.The primary UE 610 can generate a priority secondary UE list indicatingan order of preference of using secondary UEs as a clone pair in caseswhere more than one secondary UE is discovered.

The pairing information can include information that can be used by thesecondary UE 620 to clone the primary UE 610. The pairing informationmay include information identifying the primary UE 610 such as precodinginformation, a UE subscriber identifier (ID), or an assigned InternetProtocol (IP) address. The pairing information may include anidentification of a type and/or an amount of data expected to betransmitted and/or received via the clone pairing. In someimplementations, the pairing information may identify a desired activeset of one or more serving nodes.

The primary UE 610 can initiate a pair request. In event 644, theprimary UE 610 can transmit a pairing request to the secondary UE 620.The pairing request can include pairing information generated at event642. In cases where multiple secondary UEs are discovered, the primaryUE 610 may transmit a message to the top candidate secondary UE and waita pre-determined period of time for an acknowledgement. The topcandidate secondary UE can have the highest joint spectral efficiencywith the primary UE 610 of the possible clone pairs. The primary UE 610can prioritize candidate secondary UEs based on one or more operationalcharacteristics of a secondary UE and/or based on one or more pairingmetrics associated with the secondary UE. One or more of operationalcharacteristics and/or one or more of the pairing metrics described inassociation with the secondary UE 620 determining whether to accept therequest can be used by the primary UE 610 in prioritizing candidatesecondary UEs. If an acknowledgement is not received from the topcandidate secondary UE, the primary UE 610 can continue to the nextcandidate in the priority peer list until an acknowledgement isreceived. If no acknowledgement is received from any candidate secondaryUE, the message flow 600 can terminate and/or start over.

In event 646, the secondary UE 620 can determine whether to accept theclone pairing request. The determination may include evaluating the typeand/or amount of data expected via the clone pairing. The determinationmay compare the expectations to the resources desired by the secondaryUE 620 to support its own operations. The determination may includedetecting an operational characteristic of the secondary UE 620, such aspower level (e.g., battery power), processor load, memory, applicationsexecuting on the secondary UE 620, existing clone pairings with otherUEs, MIMO capabilities, traffic state of the secondary UE 620 (e.g.,whether the secondary UE 620 is idle or actively communicating with thenetwork system 630), a channel condition associated with the secondaryUE 620, or another detectable operational metric for the secondary UE620. In some implementations, the operational characteristic may becompared to a threshold and if the characteristic satisfies thethreshold, the determination may indicate the secondary UE 620 is ableto establish clone pairing with the primary UE 610. In certainapplications, a plurality of operational characteristics can each becompared to a respective threshold, and the determination of whether toaccept a clone pairing request can be based on the comparisons. Thedetermination can be made based on some or all of the operationalcharacteristics satisfying respective thresholds.

The determination can be based on one or more of a variety of factors.For example, the determination can be based on one or more pairingmetrics. Example pairing metrics include one or more lists associatedwith a user equipment such as a social network list, one or more apriori agreements, or incentives such as tokens provided for serving ina clone pair. Example incentives include cellular data allowancetransfer from the primary UE, digital cash, or credit tokens associatedwith a social network service. In some instances, a pairing can be basedon one or more explicit (e.g., group of users who have agreed tocooperate) or implicit a priori agreements (e.g., a friend list or listof users with common interest defined by social network service). Inresponse to determining to establish a clone pair, the secondary UE 620can send a confirmation to the primary UE 610 at event 648. If thepairing request is not granted by the secondary UE 620, the primary UE610 can send a pairing request to the next highest secondary UE on thepriority list.

In response to the secondary UE 620 confirming the paring request atevent 648, the primary UE 610 and the secondary UE 620 can establish aclone pair. A P2P link can be established between the primary UE 610 andthe secondary UE 620. The primary UE 610 can request CQI and/orprecoding information from the secondary UE 620. The secondary UE 620can estimate its own cellular channel information and provide thecellular channel information, such as channel state quality and/orchannel noise estimates, to the primary UE 610 via the P2P link.

In event 650, the primary UE 610 can generate a joint channel reportincluding cellular channel information for the primary UE 610 and thesecondary UE 620. The joint channel report can include any suitablejoint channel information. For example, the joint channel report caninclude one or more of a joint CQI, rank, or precoding selection. Thejoint CQI, rank, and/or precoding selection can be computed based oninformation associated with the primary UE 610 and informationassociated with the secondary UE 620.

The primary UE 610 can transmit the joint channel report to the networksystem 630 at event 652. Alternatively or additionally, the secondary UE620 can transmit the joint channel report to the network system 630. Thetransmission of the joint channel report may occur via a cellularchannel to one or more TRPs. The joint channel report can beperiodically generated and transmitted to the network system 630 incertain applications.

The network system 630 can serve traffic associated with the primary UE610 based on the joint channel report. The network system 630 can servethe primary UE 610 based on the paired CQI of the primary UE 610 and thesecondary UE 620. The network system 630 can schedule and transmitcellular communications with the primary UE 610 and the secondary UE620.

The network system 630 can send a first cellular communication to theprimary UE 610 at event 654. The first cellular communication caninclude a first part of a MIMO transmission to the primary UE 610. Thenetwork system 630 can send a second cellular communication to thesecondary UE 620 at event 658. The second cellular communication caninclude a second part of the MIMO transmission to the primary UE 610.The second cellular communication can be concurrent with the firstcellular communication. Accordingly, the network system 630 can servetraffic to the primary UE 610 and the secondary UE 620 concurrently. Thefirst part and the second part of the MIMO transmission can includeinformation indicating the respective cellular communications areassociated with the primary UE 610. The information can include anidentifier or hash code, for example. The information may be implied bya timing slot or frequency used to transmit the cellular communications.

The secondary UE 620 can determine that the second part of the MIMOtransmission includes a communication for the primary UE 610. Thesecondary UE 620 can provide the second part of the MIMO transmission tothe primary UE 610 via the P2P link at event 660. The secondary UE 620can pass the second part of the MIMO transmission directly over the P2Plink. In certain applications, the P2P link between the primary UE 610and the secondary UE 620 can preferably occur over an air interface witha relatively short range, such as Bluetooth, Wi-Fi, ZigBee, or otherstandardized or proprietary local area network protocol. The P2P linkbetween the primary UE 610 and the secondary UE 620 can enable cellularcommunications, such as cellular communications at relatively highfrequencies. In certain applications, the second part of the MIMOtransmission can be encapsulated, modified, or otherwise reformattedinto a format suitable for transmission via the peer-to-peer channel.

After event 660, the primary UE 610 can jointly process the first partof the MIMO transmission and the second part of the MIMO transmission.

The primary UE 610 and the secondary UE 620 can also jointly send uplinkMIMO data from the primary UE 610 to the network 630. Similar events andcommunications can be implemented for uplink communications. Forexample, the primary UE 610 may transmit cellular communications to thenetwork system 630 via a cellular interface and to the secondary UE 620via the peer-to-peer link. The secondary UE 620 may, in turn, transmitthe received communication to the network system 630. In someimplementations, the uplink transmissions to the network system 630 fromthe primary UE 610 and the secondary UE 620 may be coordinated (e.g.,time, frequency, and/or spatial). The coordination may be specifiedduring the pairing process.

The pairing may be terminated based on changed network conditions. Forexample, the primary UE 610 may detect channel degradation for thesecondary UE 620 or a change in state (e.g., traffic state change, lowbattery) of secondary UE 620. Control messages may be exchanged betweenthe primary UE 610 and the secondary UE 620 to indicate one or more suchchanging conditions. It may be desirable for the primary UE 610 totransmit a channel report identifying a single-user mode beforedisassociating with the secondary UE 620. In some implementations, theprimary UE 610 may be limited to one active clone pairing. Accordingly,if a better secondary UE is detected (e.g., stronger signal strength,power level, etc.), the primary UE 610 may first disassociate from thesecondary UE 620 before initiating a clone pairing with the bettersecondary UE.

In the message flow 600 shown in FIG. 6, the primary UE 610 may assesswhether and which secondary UE to request to be in a clone pair. In someimplementations, a network system may assist and/or direct a clonepairing.

FIG. 7 illustrates example communications and events of an embodiment ofestablishing a clone pair of UEs and jointly receiving MIMO dataassociated with one UE of the clone pair using both UEs of the clonepair. The communications and events of FIG. 7 relate to a tightlycoupled mode in which a primary UE 710 and a secondary UE 720 share anidentity as a clone pair. In the communications and events of FIG. 7, anetwork system 730 makes a determination to pair the primary UE 710 andthe secondary UE 720 as a clone pair. The message flow 700 illustratesexample communications and events associated with a primary userequipment 710, a secondary user equipment 720, and a network system 730.The primary UE 710 can implement any suitable features of the UEsdisclosed herein. The secondary UE 720 can implement any suitablefeatures of the UEs disclosed herein. The network system 730 can includea base band unit or other network device configured to schedulecommunications with devices within a service area. Additional oralternative entities may be include to mediate one or more of theinteractions shown such as network routers, switches, security devices,or the like.

In event 740, the primary UE 710 can discover the secondary UE 720. Thediscovery may include receiving, at the primary UE 710 a message fromthe secondary UE 720. In some implementations, the discovery may be abroadcast discovery whereby the message is generally transmitted todevices within a range of the primary UE 710. The discovery may includepeer-to-peer beacons and/or signals. The message may include informationindicating clone pairing capabilities. In such instances, devices thatcan perform clone pairing may respond. Although shown as discovering asingle secondary UE in FIG. 7, the primary UE 710 may discover two ormore secondary UEs with which it may establish a clone pairing. Thesecondary UE 720 may be within the same cell as the primary UE 710. Insome instances, the secondary UE 720 and the primary UE 710 can beserved by different TRPs within the same cell.

The primary UE 710 can collect information associated with the secondaryUE 720. For example, the primary UE 710 can collect one or more ofavailability of the secondary UE 720 to serve as a secondary UE for theprimary UE 710, recent CQI information, precoding selection, or thelike. The primary UE 710 can store the collected information associatedwith the secondary UE 720. The primary UE 710 can collect and storeinformation associated with a plurality of secondary UEs 720.

After discovering the secondary UE 720, the primary UE 710 may generatepairing information at block 742. The primary UE 710 can compute a jointspectral efficiency of the primary UE 710 and the secondary UE 720operating as a clone pair. The computation of spectral efficiency can bebased on information collected associated with discovering the secondaryUE in event 740. The UE pairing information can include the jointspectral efficiency. The joint spectral efficiency and/or other pairinginformation can be computed for one or more additional secondary UEs.The primary UE 710 can generate a priority secondary UE list indicatingan order of preference of using secondary UEs in a clone pair in caseswhere more than one secondary UE is available.

The pairing information can include information that can be used by thesecondary UE 720 to clone the primary UE 710. The pairing informationmay include information identifying the primary UE 710 such as precodinginformation, a UE subscriber ID, or an assigned Internet Protocol (IP)address. The pairing information may include an identification of a typeor amount of data expected to be transmitted or received via the clonepairing. In some implementations, the pairing information may identify adesired active set of one or more serving nodes.

The primary UE 710 can transmit UE pairing information to the networksystem 730 at event 744. Because the network system 730 can detectconditions of the network which may not be accessible to the primary UE710, the network system 730 may use the increased information todetermine the clone pairing for the primary UE 710. In event 746, thenetwork system 710 can determine a clone pair. The network system 730can update the priority secondary UE list. In the example of FIG. 7, theclone pair includes the primary UE 710 and the secondary UE 720. Thenetwork system 730 can determine the clone pair based on the UE pairinginformation transmitted at event 744. For example, the network system730 can determine the clone pair based on joint spectral efficiency of apair of UEs.

The network system 730 can also take into account other networkinformation in determining the clone pair at event 746. The othernetwork information can include information identifying the mobility ofsecondary UEs. For example, the primary UE 710 may determine that aspecific secondary UE has a particularly strong signal strength but,unbeknownst to the primary UE 710, is that the specific secondary UE islocated on a moving vehicle that is likely to soon exceed a desireddistance range for clone pairing. The network system 730 can use acriterion based on a set of metrics of the primary UE 710, the secondaryUE 710, or/or other UEs served by the network system to determine thebest operating regime to serve the primary UE 710. The metrics caninclude a device mobility state, a Doppler estimate, a measure of thenetwork-to-UE channel matrix condition such as Eigen-value spread, anetwork congestion measure (e.g., network load), the like, or anysuitable combination thereof. The metrics can include one or moreoperational characteristics of the secondary UE 720 and/or one or morepairing metrics. In a tightly coupled mode, the uplink transmissionsfrom both the primary UE 710 and the secondary UE 720 can appear as onetransmission from the primary UE 710. This can be indicated by channelassignment and/or signaling overhead.

If the clone pairing result from event 746 is not to establish a clonepair (e.g., no secondary UEs were available for pairing), the messageflow 700 can terminate and/or start over. In such instances, the networksystem 730 may transmit a message to the primary UE 710 that a clonepair is not being established.

In the message flow 700 shown in FIG. 7, the secondary UE 720 isidentified by the network system 730 for pairing with the primary UE710. The network system 730 may communicate the identified pairinginformation to the primary UE 710 in event 748. This can involve sendinga clone pairing command. The pairing information may include anidentifier for the secondary UE 720. In some implementations, thepairing information may include a security token and/or otherauthentication information to verify the pairing as being performed byone or more parties authorized by the network system 730. The clonepairing command can signal to the primary UE 710 to initiate a P2P linkwith a particular secondary UE 720. In some instances, the network 730can provide information identifying a priority list of secondary UEs toestablish a P2P link with and an order to try establishing the P2P link.

The primary UE 710 can transmit a clone pairing request to the secondaryUE 720 at event 750. Then the secondary UE 720 can enter a clone mode.The secondary UE 720 can send a confirmation to the primary UE 710 thatthe secondary UE 720 accepts the request to enter the clone mode atevent 752. In some instances, the secondary UE 720 can also send aconfirmation to the network system 730. Unlike in FIG. 6, the secondaryUE 720 can depend on the determination of the network system 730 whenaccepting the request for pairing. In some implementations, thesecondary UE 720 may perform some confirmation of its ability to be partof clone pair (e.g., detecting that it has sufficient power).

A P2P communication channel can be established between the primary UE710 and the secondary UE 720 for clone traffic to and/or from theprimary UE 710. In the clone mode, the secondary UE 720 can estimate itsown channel information and provide the channel information estimate tothe primary UE 710 via the P2P link. The channel information can includecellular channel information for the secondary UE 720, such as channelstate quality and/or channel noise estimates.

In event 754, the primary UE 710 can generate a joint channel report forthe primary UE 710 and the secondary UE 720. The joint channel reportcan include any suitable joint channel information. For example, thejoint channel report can include one or more of a joint CQI, rank, orprecoding selection. The joint QCI, rank, and/or precoding selection canbe computed based on information associated with the primary UE 710 andinformation associated with the secondary UE 720. The joint channelreport can appear to the network system 730 as if were associated with asingle UE when in fact the primary UE 710 and secondary UE 720 areoperating as a clone pair.

The primary UE 710 can transmit the joint channel report to the networksystem 730 at event 756. Alternatively or additionally, the secondary UE720 can transmit the joint channel report to the network system 730. Thetransmission of the joint channel report may occur via a cellularchannel to one or more TRPs. The joint channel report can beperiodically generated and transmitted to the network system 730 incertain applications.

The network system 730 can serve traffic associated with the primary UE710 based on the joint channel report. The network system 730 can servethe primary UE 710 based on the paired CQI of the primary UE 710 and thesecondary UE 720.

The network system 730 can send a first cellular communication to theprimary UE 710 at event 756. The first cellular communication caninclude a first part of a MIMO transmission to the primary UE 710. Thenetwork system 730 can send a second cellular communication to thesecondary UE 720 at event 760. The second cellular communication caninclude a second part of the MIMO transmission to the primary UE 710.The second cellular communication can be concurrent with the firstcellular communication. Accordingly, the network system 730 can servetraffic to the primary UE 710 and the secondary UE 720 concurrently. Thefirst part and the second part of the MIMO transmission can includeinformation indicating the respective cellular communications areassociated with the primary UE 710. The information can include anidentifier or hash code, for example. The information may be implied bya timing slot or frequency used to transmit the cellular communications.

The secondary UE 720 can determine that the second part of the MIMOtransmission includes a communication for the primary UE 710. Thesecondary UE 720 can provide the second part of the MIMO transmission tothe primary UE 710 via the P2P link at event 762. The secondary UE 720can pass the second part of the MIMO transmission directly over the P2Plink. The P2P link between the primary UE 710 and the secondary UE 720can preferably occur over an air interface with a relatively shortrange, such as Bluetooth, Wi-Fi, ZigBee, or other standardized orproprietary local area network protocol. In certain applications, thesecond part of the MIMO transmission can be encapsulated, modified, orotherwise reformatted into a format suitable for transmission via thepeer-to-peer channel.

After event 762, the primary UE 710 can jointly process the first partof the MIMO transmission and the second part of the MIMO transmission.

The primary UE 710 and the secondary UE 720 can also jointly send uplinkMIMO data from the primary UE 710 to the network 730. Similar events andcommunications can be implemented for uplink communications. Forexample, the primary UE 710 may transmit cellular communications to thenetwork system 730 via a cellular interface and to the secondary UE 720via the peer-to-peer link. The secondary UE 720 may, in turn, transmitthe received communication to the network system 730. In someimplementations, the uplink transmissions to the network system 730 fromthe primary UE 710 and the secondary UE 720 may be coordinated (e.g.,time, frequency, and/or spatial). The coordination may be specifiedduring the pairing process. In a tightly coupled mode, the uplinktransmissions from both the primary UE 710 and the secondary UE 720 canappear as one transmission from the primary UE 710. This can beindicated by channel assignment and/or signaling overhead.

The pairing may be terminated based on changed network conditions and/ora change in a UE condition, such as mobility or available battery. Forexample, the primary UE 710 may detect channel degradation for thesecondary UE 720 or a change in state (e.g., traffic state change, lowbattery) of secondary UE 720. Control messages may be exchanged betweenthe primary UE 710 and the secondary UE 720 to indicate one or more suchchanging conditions. It may be desirable for the primary UE 710 totransmit a channel report identifying a single-user mode beforedisassociating with the secondary UE 720. In some implementations, theprimary UE 710 may be limited to one active clone pairing. Accordingly,if a better secondary UE is detected (e.g., stronger signal strength,power level, etc.), the primary UE 710 may first disassociate from thesecondary UE 720 before initiating a clone pairing with the bettersecondary UE.

FIGS. 6 and 7 illustrate a tight coupling between a primary UE and asecondary UE. The tightly coupled mode can be characterized, at least inpart, by how the UEs appear to the network system. From the perspectiveof the network system, the primary UE and the secondary UE can appear asa single transmit-receive device. This can allow the network system andthe primary UE to exchange information at higher rates and/or withhigher MIMO rank because of the aggregation of antennas across theprimary and secondary UEs.

Loosely Coupled Mode

In some implementations, it may be desirable to allow each UE of a clonepair to maintain its own identity, but increase the rate by tunneling.In such instances, first data may be transmitted to the primary UE alonga first beam and second data may be transmitted to the secondary UEalong a second beam. The secondary UE may then transfer the second datato the primary UE through a cloned peer connection. This tunnelingarrangement may be referred to a loose coupling.

In a loosely coupled pair of UEs, the primary UE and the secondary UEcan have different identities from a network perspective. The primary UEcan establish a dual connectivity (DC) tunnel through the secondary UE.TRPs of a network system can serve both the primary UE and the secondaryUE in MU-MIMO operation. A long term evolution-new radio (LTE-NR) DCprotocol, for example, can be leveraged by the primary UE to aggregateMIMO data. Aggregation can be performed at a higher layer. For example,a Packet Data Convergence Protocol (PDCP), an application layer (reuseDC protocol), or a radio link control (RLC) protocol can be used inaggregating data by the primary UE. Example operations for tightlycoupled UE pairs are discussed with reference to FIG. 8.

For a loosely coupled mode, the clone process can be initiated while theprimary UE is in a traffic state. The primary UE may determine todissociate the P2P link with the secondary UE in response to detectingchannel degradation of the secondary UE. The primary UE may determine todissociate the P2P link with the secondary UE in response to detecting achange in state of the secondary UE (e.g., a traffic state change, lowbattery mode, etc.). Tunnel set up and tear down protocol can leveragean LTE DC protocol. The primary UE can tear down a tunnel before settingup a new tunnel.

Clone paring candidate consideration in a loosely coupled mode can bebased on a UE centric discovery based on P2P beacon measurement. A clonepair candidate can be in an idle state or in an active state. Networkassisted discovery with a list of available idle secondary UEs can beimplemented. Tunnel association can be implemented between UEsconnection to the same cell or two or more different cells.

FIG. 8 illustrates example communications and events of an embodiment ofestablishing a clone pair of UEs and a tunnel to a primary UE through asecondary UE. The communications and events of FIG. 8 relate to aloosely coupled mode in which a primary UE 810 and a secondary UE 820can retain separate identities from the perspective of the network. Inthe communications and events of FIG. 8, the clone pair decision is UEcentric. The message flow 800 illustrates example communications andevents associated with a primary user equipment 810, a secondary userequipment 820, and a network system 830. The primary UE 810 canimplement any suitable features of the UEs disclosed herein. Thesecondary UE 820 can implement any suitable features of the UEsdisclosed herein. The network system 830 may be or include a base bandunit or other network device configured to schedule communications withdevices within a service area. Additional or alternative entities may beincluded to mediate one or more of the interactions shown such asnetwork routers, switches, security devices, or the like.

In event 840, the primary UE 810 can discover the secondary UE 820. Thediscovery may include receiving, at the primary UE 810 a message fromthe secondary UE 820. In some implementations, the discovery may be abroadcast discovery whereby a message is generally transmitted todevices within a range of the primary UE 810. The discovery may includepeer-to-peer beacons and/or signals. The message may include informationindicating clone pairing capabilities. In such instances, devices thatcan perform clone pairing may respond. Although shown as discovering asingle secondary UE in FIG. 8, the primary UE 810 may discover two ormore secondary UEs with which it could establish a clone pairing. Thesecondary UE 820 may be within the same cell as the primary UE 810. Insome instances, the secondary UE 820 and the primary UE 810 can beserved by different TRPs within the cell.

The primary UE 810 can collect information associated with the secondaryUE 820. For example, the primary UE 810 can collect one or more ofavailability of the secondary UE 820 to serve as a secondary UE for theprimary UE 810, recent channel quality indicator (CQI) information,precoding selection, or the like. The primary UE 810 can store thecollected information associated with the secondary UE 820. The primaryUE 810 can collect and store information associated with a plurality ofsecondary UEs 820.

After discovering the secondary UE 820, the primary UE 810 may generatepairing information at event 842. The primary UE 810 can compute a jointspectral efficiency of the primary UE 810 and the secondary UE 820operating as a clone pair. The computation of spectral efficiency can bebased on information collected associated with discovering the secondaryUE in event 840. The primary UE 810 can compute an incremental spectralefficiency that can be gained due to communicating with a network systemvia the P2P link with the secondary UE. The incremental spectralefficiency can be computed based on a P2P link condition and one or morechannel conditions of the secondary UE. The UE pairing information caninclude the joint spectral efficiency and/or the incremental spectralefficiency. UE pairing information can be computed for one or moreadditional secondary UEs. The primary UE 810 can generate a prioritysecondary UE list indicating an order of preference of using secondaryUEs as a clone pair in cases where more than one secondary UE isavailable.

The pairing information can include information that can be used by thesecondary UE 820 to clone the primary UE 810. The pairing informationmay include information identifying the primary UE 810 such as precodinginformation, a UE subscriber ID, or an assigned Internet Protocol (IP)address. The pairing information may include an identification of a typeand/or an amount of data expected to be transmitted and/or received viathe clone pairing. In some implementations, the pairing information mayidentify a desired active set of one or more serving nodes.

The primary UE 810 can initiate a pair request. In event 844, theprimary UE 810 can transmit a pairing request to the secondary UE 820.The pairing request can include pairing information generated at event842. In cases where multiple secondary UEs are discovered, the primaryUE 810 may transmit a message to the top candidate secondary UE and waita pre-determined period of time for an acknowledgement. The topcandidate secondary UE can have the highest joint spectral efficiencywith the primary UE 810 of the possible clone pairs. The primary UE 810can prioritize candidate secondary UEs based on one or more operationalcharacteristics of a secondary UE and/or based on one or more pairingmetrics associated with the secondary UE. One or more of operationalcharacteristics and/or one or more of the pairing metrics described inassociation with the secondary UE 820 determining whether to accept therequest can be used by the primary UE 810 in prioritizing candidatesecondary UEs. If an acknowledgement is not received from the topcandidate secondary UE, the primary UE 810 can continue to the nextcandidate in the priority peer list until an acknowledgement isreceived. If no acknowledgement is received from any candidate secondaryUE, the message flow 800 can terminate and/or start over.

In event 846, the secondary UE 820 can determine whether to accept theclone pairing request. The determination may include evaluating the typeand/or amount of data expected via the clone pairing. The determinationmay compare the expectations to the resources needed by secondary UE 820to support its own operations. The determination may include detectingan operational characteristic of the secondary UE 820 such as powerlevel (e.g., battery power), processor load, memory, applicationsexecuting on the secondary UE 820, existing clone pairings with otherUEs, MIMO capabilities, traffic state of the secondary UE 820 (e.g.,whether the secondary UE 820 is idle or actively communicating with thenetwork system 830), a channel condition associated with the secondaryUE 820, or another detectable operational metric for the secondary UE820. In some implementations, the operational characteristic may becompared to a threshold and if the characteristic satisfies thethreshold, the determination may indicate the secondary UE 820 is ableto establish clone pairing with the primary UE 810. In certainapplications, a plurality of operational characteristics can each becompared to a respective threshold, and the determination of whether toaccept a clone pairing request can be based on the comparisons. Thedetermination can be made based on some or all of the operationalcharacteristics satisfying respective thresholds.

The determination can be based on one or more of a variety of factors.For example, the determination can be based on one or more pairingmetrics. Example pairing metrics include one or more lists associatedwith a user equipment such as a social network list, one or more apriori agreements, or incentives such as tokens provided for serving ina clone pair. Example incentives include cellular data allowancetransfer from the primary UE, digital cash, or credit tokens associatedwith a social network service. In response to determining to establish aclone pair, the secondary UE 820 can send a confirmation to the primaryUE 810 at event 848. If the pairing request is not granted by thesecondary UE 820, the primary UE 810 can send a pairing request to thenext highest secondary UE on the priority list.

In response to the secondary UE 820 confirming the paring request atevent 848, the primary UE 810 and the secondary UE 820 can establish aclone pair. A P2P link can be established between the primary UE 810 andthe secondary UE 820. The primary UE 810 can request CQI and/orprecoding information from the secondary UE 820. The secondary UE 820can estimate its own cellular channel information and provide thecellular channel information, such as channel state quality and/orchannel noise estimates, to the primary UE 810 via the P2P link.

Unlike message flows in the examples of FIGS. 6 and 7, the message flow800 does not include generating and providing a joint channel reportbecause the primary UE 810 and the secondary UE 820 can retain theiridentities from the perspective of the network system 830. Instead, inevent 850, the primary UE 810 requests a tunnel from the network system830 through the secondary UE 820 to the primary UE 810. The tunnel canbe a DC tunnel in accordance with a DC tunnel protocol. The tunnelrequest can include information identifying the primary UE 810 and thesecondary UE 820. In some instances, the tunnel request can includesecurity information for establishing the tunnel such as encryptioninformation for data communicated via the tunnel.

In event 852, the network system 830 can determine whether to establishthe tunnel. If the network system 830 determines to establish thetunnel, the network system 830 can set up the tunnel. Because thenetwork system 830 can detect conditions of the network which are notaccessible to the primary UE 810, the network system 830 can use theadditional information to determine whether and/or how to tunnel withthe primary UE 810. The determination may include identifying themobility of secondary UE 820. The network system 830 can use a criterionbased on a set of metrics of the primary UE 810, the secondary UE 820,or/or other UEs served by the network system 830. The metrics caninclude a device mobility state, a Doppler estimate, a measure of thenetwork-to-UE channel matrix condition such as Eigen-value spread, anetwork congestion measure (e.g., network load), the like, or anysuitable combination thereof. One or more metrics can be modified to beconsistent with the available P2P information exchange bandwidth.

If the network system 830 determines not to establish the tunnel, themessage flow 800 can terminate and/or start over. In such instances, thenetwork system 830 may transmit a message to the primary UE 810declining the tunneling request.

In the message flow 800 shown in FIG. 8, a first part of a tunnel isestablished through the secondary UE 820 for the network system 830 tocommunicate with the primary UE 810. The network system 830 establishthe tunnel to the secondary UE 820 at event 854. This can involvecommunicating tunneling information to the secondary UE 820. Thetunneling information may include an identifier for the primary UE 810.In some implementations, the tunneling information may include asecurity token and/or other authentication information to verify thetunnel as being performed by one or more parties authorized by thenetwork system 830.

A second part of the tunnel can be established between the primary UE810 and the secondary UE 820 in event 856. The second part of the tunnelmay be established over a peer-to-peer air interface for relativelyshort distance communications such as Bluetooth or another standardizedor proprietary local area network protocol. In some implementations,establishing of the tunnel may be achieved according to an LTEdual-connectivity protocol, an LTE-Wi-Fi offload protocol, a LTE directprotocol, or another suitable standardized or proprietary networktunneling protocol.

Once the tunnel is established from the network system 830 to theprimary UE 810, the secondary UE 820 can pass along downlinkcommunications received via the tunnel to the primary UE 810 and uplinkcommunications received via the tunnel to the network system 830.Communications between the secondary UE 820 and the network system 830can be over a cellular link while the communications between thesecondary UE 820 and the primary UE 810 can be via the peer-to-peer airinterface. Accordingly, the secondary UE 820 can use differentcommunication technologies for communicating with the primary UE 810 andthe network system 830. Alternatively or additionally, the secondary UE820 can use different communication frequencies for communicating withthe primary UE 810 and the network system 830.

The primary UE 810 may aggregate first cellular data received directlyfrom the network system 830 with second data received from the secondaryUE 820 via the tunnel.

The primary UE 810 may determine to tear down the tunnel in response todetecting changed conditions. For example, the primary UE 810 may detectchannel degradation of secondary UE 820 and/or a change of state (e.g.,traffic state change, low battery) for the secondary UE 820. In someimplementations, the primary UE 810 may tear down an established tunnelwhen a more efficient secondary UE is detected. In such instances, theprimary UE 810 may tear down the established tunnel before setting up anew tunnel, such as via one or more of the messages shown in the messageflow 800.

Providing Different Spatial Beams to UEs of a Clone Pair

In certain embodiments, a secondary UE of a clone pair can wirelesslycommunicate with different beams and/or TRPs of a network system than aprimary UE of the clone pair. This can enable the clone pair tocommunicate with the network system at a higher data rate and/or withhigher MIMO rank than the primary UE is able to communicate with thenetwork system operating alone. Any suitable principles and advantagesdisclosed herein can be applied to using different spatial beams from anetwork system to communicate with a clone pair. The primary UE and thesecondary UE can communicate with the same serving node via respectivedifferent beams to thereby increase a data rate and/or MIMO rank.

FIG. 9A illustrates an example MIMO communications environment 900 inwhich different beams from the same serving node are transmitted todifferent UEs of a pair of UEs in communication via a P2P link. Theillustrated MIMO communication environment 900 includes a BBU 110, afirst RRU 902, a second RRU 904, a primary UE 920, and a secondary UE930.

The first RRU 902 can transmit a plurality of spatial beams, such as theillustrated beams A₁, A₂, A₃, and A₄. Similarly, the second RRU 904 cantransmit a plurality of spatial beams, such as the illustrated beams B₁,B₂, B₃, B₄, and B₅. The primary UE 920 and the secondary UE 930 can eachreceive different beams from the first RRU 902 and the second RRU 904.For example, the primary UE 920 can receive beams A₁ and B₂ and thesecondary UE 930 can receive beams A₄ and B₁. Accordingly, beams can bespatially multiplexed to communicate with the primary UE 920 and thesecondary UE 930. This can enable the primary UE 920 and the secondaryUE 930 to receive data associated with the primary UE 920 over differentspatial beams. The secondary UE 930 can provide data received for theprimary UE 920 to the primary UE 920 over a P2P link. Cellularcommunications with the primary UE 920 and the secondary UE 930 usingdifferent spatial beams can increase the data rate and/or rank of dataassociated with the primary UE 920 being transmitted by the networksystem.

Similar principles and advantages can be applied to using differentspatial beams for transmitting uplink data associated with the primaryUE 920 using the primary UE 920 and the secondary UE 930.

FIG. 9B illustrates an example MIMO communications environment 950 inwhich different beams from a single serving node are transmitted todifferent UEs of a pair of UEs in communication via a P2P link. Theillustrated MIMO communication environment 950 includes a BBU 110, anRRU 902, a primary UE 920, and a secondary UE 930. FIG. 9B illustratesthat different beams of a single TRP can serve paired UEs. The primaryUE 920 and the secondary UE 930 can each receive different beams fromthe RRU 902. Each of the paired UEs can receive a single beam in certaininstances. As illustrated, the primary UE 920 can receive beam A₁ fromthe RRU 902 and the secondary UE 930 can receive beam A₄ from the RRU902. The secondary UE 930 can provide data received for the primary UE920 to the primary UE 920 over a P2P link. Then the received dataassociated with beams A₁ and A₄ can be aggregated by the primary UE 902.Similar principles and advantages can be applied to using differentspatial beams for transmitting uplink data associated with the primaryUE 920 using the primary UE 920 and the secondary UE 930.

Methods of Wireless Communication with Clone Pair

FIG. 10A is a flow diagram illustrating an example method 1000 ofprocessing downlink data by a primary user equipment according to anembodiment. The method 1000 can be performed by any suitable UEdisclosed herein. Any suitable principles and advantages associated withthe message flow diagrams of FIGS. 6 to 8 can be implemented in themethod 1000. The method 1000 relates to aspects of a primary UEprocessing MIMO data received from a serving node and a secondary UE.

At block 1004, a first part of the MIMO downlink data transmission fromone or more serving nodes is received by the primary UE. The first partof the MIMO downlink data transmission can be received by one or moreantennas of the primary UE. The first part of the MIMO downlinktransmission can be received via a cellular link. A second part of theMIMO downlink data transmission can be received from a secondary UEusing a peer-to-peer wireless interface at block 1006. The part of theMIMO downlink data transmission can be received by a non-cellularcommunication over a P2P communication channel between the primary UEand the secondary UE.

The primary UE can process the first part of the MIMO communicationtogether with the second part of the MIMO communication at block 1008.The primary UE can include one or more antennas configured to receiveMIMO downlink data at up to a downlink peak data rate. The processing atblock 1008 can be performed such that the MIMO downlink datatransmission is processed at a higher data rate than the downlink peakdata rate. The primary UE can include antennas configured to receiveMIMO downlink data at up to a rank of N, wherein N is a positive integer2 or greater. The first and second parts of downlink MIMO datatransmission can together have a rank of greater than N. Accordingly,the processing at block 1008 can involve processing a downlink MIMO datatransmission having a rank of greater than N.

FIG. 10B is a flow diagram illustrating an example method 1010 oftransmitting uplink data by a primary user equipment according to anembodiment. The method 1010 can be performed by any suitable UEdisclosed herein. Any suitable principles and advantages associated withthe message flow diagrams of FIGS. 6 to 8 can be implemented in themethod 1010. The method 1010 relates to aspects of a primary UEtransmitting MIMO data to both a serving node and a secondary UE. Anysuitable features of the method 1010 can be implemented in combinationwith any principles and advantages of the method 1000 of FIG. 10A.

At block 1014, a communication channel is established between a primaryUE and the secondary UE. The communication channel can be establishedvia a peer-to-peer wireless interface of the primary UE. Non-cellularcommunications can be transmitted and received over the communicationchannel. The primary UE can transmit a first part of MIMO uplink data toone or more serving nodes at block 1016. The transmission to the one ormore serving nodes can be a cellular communication. The first part ofthe MIMO uplink data can be transmitted while the primary UE is incommunication with the secondary UE via the communication channelestablished at block 1014. The primary UE can also transmit a secondpart of the MIMO uplink data to a secondary UE over the communicationchannel with the secondary UE at block 1018. The transmission to thesecondary UE can be a non-cellular communication. The secondary UE canthen transmit the second part to the MIMO uplink data to one or moreserving nodes.

The method 1010 can enable the primary UE to transmit uplink data to anetwork system at a higher data rate and/or higher MIMO rank. Theprimary UE can include one or more antennas configured to transmit MIMOdownlink data at up to an uplink peak data rate. The transmissions atblocks 1016 and 1018 can be performed such that the primary UEeffectively transmits MIMO uplink data transmission to a network systemat a higher data rate than the uplink peak data rate. The primary UE caninclude antennas configured to transmit MIMO downlink data at up to arank of N, wherein N is a positive integer 1 or greater. Thetransmissions at blocks 1016 and 1018 can be performed such that theprimary UE effectively transmits uplink MIMO data a rank of greater thanN.

FIG. 11A is a flow diagram illustrating an example method 1100 ofprocessing downlink data by a secondary user equipment according to anembodiment. The method 1100 can be performed by any suitable UEdisclosed herein. Any suitable principles and advantages associated withthe message flow diagrams of FIGS. 6 to 8 can be implemented in themethod 1100. The method 1100 relates to aspects of a secondary UEreceiving MIMO data for a primary UE and transmitting the MIMO data tothe primary UE.

At block 1104, a communication channel is established between a primaryUE and the secondary UE. The communication channel can be establishedvia a peer-to-peer wireless interface of the secondary UE. Non-cellularcommunications can be transmitted and received over the communicationchannel. While the primary UE is receiving first MIMO downlink data forthe primary UE via a cellular communication, the secondary UE canreceive second MIMO downlink data for the primary UE at block 1106. Thesecondary UE can receive the second MIMO downlink data via a cellularcommunication. At block 1108, the secondary UE can transmit the secondMIMO downlink data to the primary UE via the communication channel.

The primary user equipment can receive downlink MIMO data at up to amaximum first UE rank via cellular communications, and the first MIMOdownlink data and the second MIMO downlink data can are together beincluded in a MIMO downlink data transmission having a rank that ishigher than the maximum first UE rank. The secondary user equipment canreceive downlink MIMO data at up to a maximum second UE rank viacellular communications, and the first MIMO downlink data and the secondMIMO downlink data can together be included in a MIMO downlink datatransmission having a rank that is higher than the maximum second UErank.

In certain instances, the method 1100 can include generating symbollevel data from the second MIMO downlink data received at block 1106. Insuch instances, the second MIMO downlink data transmitted at block 1108can include the symbol level data.

In some instances, the method 1100 can include sending MIMO physicallayer information to the primary user equipment over the communicationchannel. The method 1100 can alternatively or additionally includedetermining to accept a pairing request from the primary user equipmentbased on an operational characteristic of the secondary user equipment,and wherein the establishing is in response to the determining.

FIG. 11B is a flow diagram illustrating an example method 1110 ofprocessing uplink data by a secondary user equipment according to anembodiment. The method 1110 can be performed by any suitable UEdisclosed herein. Any suitable principles and advantages associated withthe message flow diagrams of FIGS. 6 to 8 can be implemented in themethod 1110. The method 1100 relates to aspects of a secondary UEreceiving MIMO data from a primary UE and transmitting the MIMO data toa network system. Any suitable features of the method 1110 can beimplemented in combination with any principles and advantages of themethod 1100 of FIG. 11A.

At block 1114, a communication channel is established between a primaryUE and the secondary UE. The communication channel can be establishedvia a peer-to-peer wireless interface of the secondary UE. In certainapplications, non-cellular communications can be transmitted andreceived over the communication channel. Cellular communications can betransmitted and received over the communication channel in someapplications. While the primary UE is transmitting first MIMO uplinkdata for the primary UE to a network system via a cellularcommunication, the secondary UE can receive second MIMO uplink data fromthe primary UE via the communication channel at block 1116. At block1118, the secondary UE can transmit the second MIMO uplink data to thenetwork system.

The primary user equipment can transmit uplink MIMO data at up to amaximum first UE rank via cellular communications, and the first MIMOuplink data and the second MIMO uplink data can are together be includedin a MIMO uplink data transmission having a rank that is higher than themaximum first UE rank. The secondary user equipment can transmit uplinkMIMO data at up to a maximum second UE rank via cellular communications,and the first MIMO uplink data and the second MIMO uplink data cantogether be included in a MIMO downlink data transmission having a rankthat is higher than the maximum second UE rank.

In certain instances, the method 1110 can include generating higherlevel data from symbol level data received at block 1116. In suchinstances, the second MIMO uplink data receive and transmitted at blocks1116 and 1118, respectively, can include the different level data.

In some instances, the method 1110 can include sending MIMO physicallayer information to the primary user equipment over the communicationchannel. The method 1110 can alternatively or additionally includedetermining to accept a pairing request from the primary user equipmentbased on an operational characteristic of the secondary user equipment,and wherein the establishing is in response to the determining

FIG. 12A is a flow diagram illustrating an example method 1200 ofprocessing uplink data by a network system according to an embodiment.The method 1200 can be performed by any suitable network systemdisclosed herein. Any suitable principles and advantages associated withthe message flow diagrams of FIGS. 6 to 8 can be implemented in themethod 1200. The method 1200 relates to aspects of a network systemprocessing uplink MIMO data associated with a primary UE, in which theuplink MIMO data is received from the primary UE and a secondary UE.

At block 1204, a first uplink data transmission associated with aprimary user equipment from the primary user equipment can be receivedby a network system. The primary user equipment is configured totransmit uplink data at a rate of up to a peak uplink data rate. Thenetwork system can receive a second uplink data transmission associatedwith the primary user equipment from a secondary user equipment at block1206. The network system can process data associated with the first andsecond uplink data transmissions at block 1208. The processing at block1208 can be performed so as to process uplink data associated with theprimary UE at a rate of greater than the peak uplink data rate of theprimary UE.

FIG. 12B is a flow diagram illustrating an example method 1210 oftransmitting downlink data by a network system according to anembodiment. The method 1210 can be performed by any suitable networksystem disclosed herein. Any suitable principles and advantagesassociated with the message flow diagrams of FIGS. 6 to 8 can beimplemented in the method 1210. The method 1210 relates to aspects of anetwork system transmitting downlink MIMO data associated with a primaryUE to the primary UE and a secondary UE. Any suitable features of themethod 1210 can be implemented in combination with any principles andadvantages of the method 1200 of FIG. 12A.

At block 1214, the network system can generate downlink transmissiondata for a primary UE. The network system can transmit parts of thedownlink data transmission for the primary UE to the primary UE and thesecondary UE while the primary UE and the secondary UE are incommunication with each other via a P2P link. The network system cantransmit a first part of the downlink transmission data for the primaryuser equipment to the primary user equipment at block 1216. This canoccur while the primary user equipment is in communication with asecondary user equipment via the P2P link. The network system cantransmit a second part of the downlink transmission data for the primaryuser equipment to the secondary user equipment at block 1218. This canoccur while the primary user equipment is in communication with asecondary user equipment via the P2P link.

Terminology, Applications, and Conclusion

Depending on the embodiment, certain acts, events, or functions of anyof the processes or algorithms described herein can be performed in adifferent sequence, can be added, merged, or left out altogether (e.g.,not all described operations or events are necessary for the practice ofthe algorithm). Moreover, in certain embodiments, operations, or eventscan be performed concurrently, e.g., through multi-threaded processing,interrupt processing, or multiple processors or processor cores or onother parallel architectures, rather than sequentially.

Conditional language used herein, such as “can,” “could,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements, and/or steps. Thus, suchconditional language is not generally intended to imply that features,elements, and/or steps are in any way required for one or moreembodiments or that one or more embodiments necessarily include logicfor deciding, with or without other input or prompting, whether thesefeatures, elements, and/or steps are included or are to be performed inany particular embodiment. The terms “comprising,” “including,”“having,” and the like are synonymous and are used inclusively, in anopen-ended fashion, and do not exclude additional elements, features,acts, operations, and so forth. Additionally, the words “herein,”“above,” “below,” and words of similar import, when used in thisapplication, shall refer to this application as a whole and not to anyparticular portions of this application. Where the context permits,words in the above Detailed Description of Certain Embodiments using thesingular or plural may also include the plural or singular,respectively. Also, the term “or” is used in its inclusive sense (andnot in its exclusive sense) so that when used, for example, to connect alist of elements, the term “or” means one, some, or all of the elementsin the list.

Disjunctive language such as the phrase “at least one of X, Y, Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to present that an item, term, etc., may beeither X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z).Thus, such disjunctive language is not generally intended to, and shouldnot, imply that certain embodiments require at least one of X, at leastone of Y, or at least one of Z to each be present.

Unless otherwise explicitly stated, articles such as “a” or “an” shouldgenerally be interpreted to include one or more described items.Accordingly, phrases such as “a device configured to” are intended toinclude one or more recited devices. Such one or more recited devicescan also be collectively configured to carry out the stated recitations.For example, “a processor configured to carry out recitations A, B andC” can include a first processor configured to carry out recitation Aworking in conjunction with a second processor configured to carry outrecitations B and C.

The word “coupled,” as generally used herein, refers to two or moreelements that may be either directly coupled to each other, or coupledby way of one or more intermediate elements. Likewise, the word“connected,” as generally used herein, refers to two or more elementsthat may be either directly connected, or connected by way of one ormore intermediate elements.

As used herein, the terms “determine” or “determining” encompass a widevariety of actions. For example, “determining” may include calculating,computing, processing, deriving, generating, obtaining, looking up(e.g., looking up in a table, a database or another data structure),ascertaining and the like via a hardware element without userintervention. Also, “determining” may include receiving (e.g., receivinginformation), accessing (e.g., accessing data in a memory) and the likevia a hardware element without user intervention. Also, “determining”may include resolving, selecting, choosing, establishing, and the likevia a hardware element without user intervention.

As used herein, the terms “provide” or “providing” encompass a widevariety of actions. For example, “providing” may include storing a valuein a location of a storage device for subsequent retrieval, transmittinga value directly to the recipient via at least one wired or wirelesscommunication medium, transmitting or storing a reference to a value,and the like. “Providing” may also include encoding, decoding,encrypting, decrypting, validating, verifying, and the like via ahardware element.

As used herein a “transmit-receive point” (TRP) (which can alternativelybe referred to as a transmission reception point) may refer to atransceiver device or one transceiver element included in a device. Whenincluded as a transceiver element, the device may include multiple TRPs.The TRP may include one or more antennas which are coupled to signalprocessing circuitry. The signal processing circuitry may be included inthe device. The TRP may include additional elements to facilitatetransmission or receipt of wireless signals for one or more UEs. Exampleof such elements may include a power source, amplifier,digital-to-analog converter, analog-to-digital converter, or the like.When a TRP is allocated, such as by a BBU, to provide service to a UE,the TRP may be said to be a “serving node” for the UE.

As used herein a “remote radio unit” (RRU) may refer to a device forcontrolling and coordinating transmission and receipt of wirelesssignals for one or more UEs. An RRU may include or be coupled with oneor more TRPs. The RRU may receive signals from the TRP and include thesignal processing circuitry. The signal processing circuitry may beselectively operated to facilitate processing of signals associated withdifferent TRPs.

While the above detailed description has shown, described, and pointedout novel features as applied to various embodiments, it can beunderstood that various omissions, substitutions, and changes in theform and details of the devices or algorithms illustrated can be madewithout departing from the spirit of the disclosure. For example,circuit blocks and/or method blocks described herein may be deleted,moved, added, subdivided, combined, arranged in a different order,and/or modified. Each of these blocks may be implemented in a variety ofdifferent ways. Any portion of any of the methods disclosed herein canbe performed in association with specific instructions stored on anon-transitory computer readable storage medium being executed by one ormore processors. As can be recognized, certain embodiments describedherein can be embodied within a form that does not provide all of thefeatures and benefits set forth herein, as some features can be used orpracticed separately from others. The scope of certain embodimentsdisclosed herein is indicated by the appended claims rather than by theforegoing description. All changes which come within the meaning andrange of equivalency of the claims are to be embraced within theirscope.

1. (canceled)
 2. A network system for wirelessly communicatingmultiple-input multiple-output (MIMO) data with a plurality of wirelesscommunication devices, the network system comprising: one or moreserving nodes; and a base band unit in communication with the one ormore serving nodes, the base band unit configured to cause the one ormore serving nodes to: wirelessly transmit a first part of a downlinkMIMO data transmission associated with a primary wireless communicationdevice to the primary wireless communication device, wherein the firstpart of the downlink MIMO data transmission has a rank of N, and whereinthe downlink MIMO data transmission has a rank of greater than N; andwirelessly transmit a second part of the downlink MIMO data transmissionassociated with the primary wireless communication device to a secondarywireless communication device.
 3. The network system of claim 2, whereinthe base band unit is configured to cause a tunnel to be establishedbetween the network system and the primary wireless communication devicevia the secondary wireless communication device, and wherein the baseband unit is configured to cause the one or more serving nodes towirelessly transmit the second part of the downlink MIMO datatransmission via the tunnel.
 4. The network system of claim 2, whereinthe base band unit is configured to cause the one or more serving nodesto wirelessly transmit the downlink MIMO data transmission based atleast partly on a joint channel report associated with the primarywireless communication device and the secondary wireless communicationdevice.
 5. The network system of claim 2, wherein the rank of thedownlink MIMO data transmission is a sum of the rank of the first partof the downlink MIMO data transmission and a rank of the second part ofthe downlink MIMO data transmission.
 6. The network system of claim 2,wherein the one or more serving nodes comprise a first serving node anda second serving node, the base band unit is configured to cause thefirst serving node to wirelessly transmit the first part of the downlinkMIMO transmission, and the base band unit is configured to cause thesecond serving node to wirelessly transmit the second part of thedownlink MIMO transmission.
 7. The network system of claim 6, whereinthe base band unit is configured to determine that the second servingnode is unavailable for wirelessly transmitting any of the downlink MIMOdata transmission to the primary wireless communication device.
 8. Thenetwork system of claim 2, wherein the base band unit is configured tocause a single serving node of the one or more serving nodes towirelessly transmit both the first and second parts of the downlink MIMOtransmission.
 9. The network system of claim 2, wherein the base bandunit is configured to: determine to pair the primary wirelesscommunication device and the secondary wireless communication device forcoordinated reception of downlink data; and based on the determining,cause a pairing command to be transmitted to at least one of the primarywireless commination device or the secondary wireless communicationdevice.
 10. A method of wirelessly communicating multiple-inputmultiple-output (MIMO) data, the method comprising: wirelesslytransmitting, from a network system, a first part of a downlink MIMOdata transmission associated with a primary wireless communicationdevice to the primary wireless communication device, wherein the firstpart of the downlink MIMO data transmission has a rank of N, and whereinthe downlink MIMO data transmission has a rank of greater than N; andwirelessly transmitting, from the network system, a second part of thedownlink MIMO data transmission associated with the primary wirelesscommunication device to a secondary wireless communication device. 11.The method of claim 10, further comprising establishing a tunnel betweenthe network system and the primary wireless communication device via thesecondary wireless communication device, wherein the second part of thedownlink MIMO data transmission is transmitted via the tunnel.
 12. Themethod of claim 10, further comprising: receiving, by the networksystem, a joint channel report associated with the primary wirelesscommunication device and the secondary wireless communication device;and determining, by the network system, to wirelessly transmit the firstpart of the downlink MIMO data to the primary wireless communicationdevice and wirelessly transmit the second part of the downlink MIMO datatransmission to the secondary wireless communication device.
 13. Themethod of claim 10, wherein the first part of the downlink MIMO data istransmitted from a first serving node and the second part of thedownlink MIMO data transmission is transmitted from a second servingnode.
 14. The method of claim 10, wherein the first and second parts ofthe downlink MIMO data are transmitted from a single serving node. 15.The method of claim 10, further comprising: determining to pair theprimary wireless communication device and the secondary wirelesscommunication device for coordinated reception of downlink data; andbased on the determining, transmitting a pairing command to at least oneof the primary wireless commination device or the secondary wirelesscommunication device.
 16. The method of claim 10, further comprising:receiving, by the network system, a first part of an uplink MIMO datatransmission associated with the primary wireless communication devicefrom the primary wireless communication device; receiving, by thenetwork system, a second part of the uplink MIMO data transmissionassociated with the primary wireless communication device from thesecondary wireless communication device; and jointly processing dataassociated with the first and second parts of the uplink MIMO datatransmission.
 17. A network system for wirelessly communicatingmultiple-input multiple-output (MIMO) data with a plurality of wirelesscommunication devices, the network system comprising: one or moreserving nodes configured to: receive a first part of an uplink MIMO datatransmission associated with a primary wireless communication devicefrom the primary wireless communication device; and receive a secondpart of the uplink MIMO data transmission associated with the primarywireless communication device from a secondary wireless communicationdevice; and a base band unit in communication with the one or moreserving nodes, the base band unit configured to jointly process dataassociated with the first part of the uplink MIMO data transmission andthe second part of the uplink MIMO data transmission.
 18. The networksystem of claim 17, wherein the first part of the uplink MIMO datatransmission has a rank of N, and the uplink MIMO data transmission hasa rank of greater than N.
 19. The network system of claim 17, whereinthe first part of the uplink MIMO data transmission has a rank of N, theuplink MIMO data transmission has a rank of N, and the first and secondparts of the uplink MIMO data transmission provide transmit diversity.20. The network system of claim 17, wherein the base band unit isconfigured to cause a tunnel to be established between the networksystem and the primary wireless communication device via the secondarywireless communication device, and wherein the second part of the uplinkMIMO data transmission is received via the tunnel.
 21. The networksystem of claim 17, wherein the first and second parts of the uplinkMIMO data transmission are part of a single-user MIMIO operation.